Recovering RAID5

Ok, here's the story:  I had set up a 6 disk ATA RAID5 group on a RedHat system.  Several months into using it, one of the disks went away, was marked faulty and the group was, naturally, forced into degraded mode.  Shortly thereafter a second disk went away, at which point the group, also quite naturally, would no longer activate and told me to go get my backups (there are none, btw, this is a home system sort of thing).

Here's the thing, I was having issues with the power supply on that system and it's quite possible that there is nothing wrong with these two drives or the data on them - and that they were just marked faulty because they lost power as the system was running.

I didn't have time to do anything about this debacle at the time, and that system was cannibalized for parts; now I've cobbled together a system with enough IDE controllers (and power supplies) to attach the 6 drives and see if there's anything to be done.  It's running an Ubuntu live CD.

So the question is - is it possible to mark a faulted disk "good" and just have it try to use it?

The second question is - if none of them drives were faulted, would just yanking the drives out of one system and putting them in another even work?  mdadm seems to have figured out enough from the drives to know how they are supposed to fit together, but I don't even know if that's correct.  For instance, doing an mdadm --examine shows (among other things) a list of all the drives with their old device names (id my /dev/hda1 thinks it's /dev/hdg1, etc) - does this matter, or is that just an internal label?

Basically I know very little about the linux RAID tools (originally created the group using mkraid with manual in hand), what is the relationship between mkraid and mdadm, anyway?

Thanks for the help (sorry it's a bit longwinded)