Porting users from one system to the next

So I'm constantly getting moved from server to server for a test enviroment, don't ask why cause I can't even answer that one. There are like 13 of us who require accounts on whatever server we get moved to and if the UID's don't match, it screws up too much stuff. So what I did, after having to move a couple of time, was make a copy of /etc/passwd and delete every user line that doesn't correspond to the 13 of us. I decided to script this and I thought I knew what I was doing, but somehow not only did I get lost in my own logic, but somehow I screwed it up and it actually does nothing. It may not even make any sense, so am asking for help correcting this into something that works so I can port this over when we get moved again. Here is what I wrote. If someone can help me figure out why this now just hangs at the beginning, or even help me figure out a better way of writting this. Also, I wanted to carry over the passwords for /etc/shadow, but when this didn't work, I paused until I could fix it:

#!/usr/bin/ksh
# User work script


# Step 1, Back up files for roleback.
cp /etc/passwd /etc/passwd_`date '+%m-%d-%y_%H:%M:%S'`
cp /etc/shadow /etc/shadow_`date '+%m-%d-%y_%H:%M:%S'`
cp /etc/group /etc/group_`date '+%m-%d-%y_%H:%M:%S'`

# Step 2, set needed variables.
sourcefile=/tmp/projectusers.txt
targetfile=/etc/passwd
targetfile2=/etc/group
targetfile3=/etc/shadow

# Step 3, start for/do loop to import source data
#
echo "Starting Loop of users"
for sourceusr in `cat $sourcefile | awk -F: '{print $1}'`
do
        # set variables inside of for/do loop.
        targetusr=`grep $i $targetfile | grep $sourceusr | awk -F: '{print $1}'`
        sourceuid=`cat $sourcefile | grep $sourceusr | awk -F: '{print $3}'`
        targetuid=`grep $i $targetfile | grep $sourceusr | awk -F: '{print $3}'`
        sourcegid=`cat $sourcefile | grep $sourceusr | awk -F: '{print $4}'`
        targetgid=`grep $i $targetfile | grep $sourceusr | awk -F: '{print $4}'`
        sourcedesc=`cat $sourcefile | grep $sourceusr | awk -F: '{print $5}'`
        targetdesc=`grep $i $targetfile | grep $sourceusr | awk -F: '{print $5}'`
        sourcedir=`cat $sourcefile | grep $sourceusr | awk -F: '{print $6}'`
        targetdir=`grep $i $targetfile | grep $sourceusr | awk -F: '{print $6}'`
        sourcesh=`cat | grep $sourceusr $sourcefile | awk -F: '{print $7}'`
        targetsh=`grep $i $targetfile | grep $sourceusr | awk -F: '{print $7}'`
        echo "Variables set, see below:"
        echo "-------------------------"
        echo "targetusr=$targetusr"
        echo "sourceuid=$sourceuid"
        echo "targetuid=$targetuid"
        echo "sourcegid=$sourcegid"
        echo "targetgid=$targetgid"
        echo "sourcedesc=$sourcedesc"
        echo "targetdesc=$targetdesc"
        echo "sourcedir=$sourcedir"
        echo "targetdir=$targetdir"
        echo "sourcesh=$sourcesh"
        echo "targetsh=$targetsh"
        echo
#
        # Start verification
        testusr=`grep -c $sourceusr $targetfile`
        echo "Results for $sourceusr"
        echo "============================="
        echo "Source ID=$sourceusr, while Target show: $targetusr"
        if [ $testusr -eq 0 ]
        then
                echo "Account $sourceusr does not exist, create it"
                # Verifying UID is free before creating account"
                testuid=`grep -c $sourceuid $targetfile`
                echo "Results for $sourceuid"
                echo "-----------------------------"
                echo "Source ID=$sourceuid, while Target show: $targetuid"
                if [ $testuid -eq 0 ]
                then
                        echo "UID $sourceuid is in use. You need to deal with $sourceuid manually"
                else
                        echo "UID $sourceuid is free, we can continue.."
                        # Verify that directory hasn't been created
                        if [ ! -d $sourcedir ];
                        then
                                echo "$sourcedir does not exists, you're good to go!"
                                useradd -m -d $sourcedir -u $sourceuid -g $sourcegid -s $sourcesh -c $sourcedesc $sourceusr
                        else
                                echo "$sourcedir exits, will adjust ownership."
                                useradd -m -u $sourceuid -g $sourcegid -s $sourcesh -c $sourcedesc $sourceusr
                                chown -R $sourceuid:$sourcegid $sourcedir
                                find /home -user $sourceuid -exec chown $sourceuid:$sourcegid {} \;
                                find /apps -user $sourceuid -exec chown $sourceuid:$sourcegid {} \;
                                find /project -user $sourceuid -exec chown $sourceuid:$sourcegid {} \;
                        fi
                fi
        else
                echo "Account $sourceusr exist, checking other variables"
                # Verifying if UID matches"
                if [ "sourceuid" -eq "targeruid" ]
                then
                        echo "UID $sourceuid & $target UID match."
                        # Verify directory
                        if [ ! -d $sourcedir ];
                        then
                                echo "$sourcedir does not exists, you're good to go!"
                                mkdir $sourcedir
                                chown -R $sourceuid:$sourcegid $sourcedir
                                find /home -user $sourceuid -exec chown $sourceuid:$sourcegid {} \;
                                find /apps -user $sourceuid -exec chown $sourceuid:$sourcegid {} \;
                                find /project -user $sourceuid -exec chown $sourceuid:$sourcegid {} \;
                        else
                                echo "$sourcedir exits, will adjust ownership."
                                chown -R $sourceuid:$sourcegid $sourcedir
                                find /home -user $sourceuid -exec chown $sourceuid:$sourcegid {} \;
                                find /apps -user $sourceuid -exec chown $sourceuid:$sourcegid {} \;
                                find /project -user $sourceuid -exec chown $sourceuid:$sourcegid {} \;
                        fi
                else

                        # Verifying UID is free before creating account"
                        testuid=`grep -c $sourceuid $targetfile`
                        echo "Results for $sourceuid"
                        echo "-----------------------------"
                        echo "Source ID=$sourceuid, while Target show: $targetuid"
                        if [ $testuid -eq 0 ]
                        then
                                echo "UID $sourceuid is in use. You need to deal with $sourceuid manually"
                        else
                                echo "UID $sourceuid is free, we can continue.."
                                # Verify that directory hasn't been created
                                if [ ! -d $sourcedir ];
                                then
                                        echo "$sourcedir does not exists, you're good to go!"
                                        usermod -d $sourcedir -u $sourceuid -g $sourcegid -s $sourcesh -c $sourcedesc $sourceusr
                                else
                                        echo "$sourcedir exits, will adjust ownership."
                                        usermod -u $sourceuid -g $sourcegid -s $sourcesh -c $sourcedesc $sourceusr
                                        chown -R $sourceuid:$sourcegid $sourcedir
                                        find /home -user $sourceuid -exec chown $sourceuid:$sourcegid {} \;
                                        find /apps -user $sourceuid -exec chown $sourceuid:$sourcegid {} \;
                                        find /project -user $sourceuid -exec chown $sourceuid:$sourcegid {} \;
                                fi
                        fi
                fi
        fi
done