Question about @INC variable in perl

perl -V gives you information on the @INC variable.

I'm assuming if your perl script calls a module, it is loaded in the order in which the @INC is listed (from the perl-V command)

How do I change the order of these directories so I can make sure it picks up the version of the module I'm intending? ...or, is that implied in the script itself on the first line. i.e. #!/home/mydir/perl

There are 3 versions of perl on the system, which seems to be necessary (specific to how this server is used).

Thanks