I guess you did not apply for, or take, the Apple Certified Technician course which would have opened all the manuals and information that you needed.
Of course, how you would get in to them is all dependent of information that you did not share with us.
iMac 17" is not going to cut it.
iMac G4 17", iMac G5 17", iMac Intel 17" all have different methods to get inside them.
What type of iMacs are they?
I am tech support for an Elementary-Middle school with an all Mac curriculum. We have been this way for just about 4 years now and our first model iMac 17 inches are no longer under warranty.
We have three iMac 17"s that don't work properly, here's the rundown:
- The First works properly fine but has a bad DVI port (we run SMARTBoards and require them for most of our classroom computers)
- The Second has a bad logic board, we don't have any other information about it
- The Third has a broken display, we're pretty sure everything else works on it.
We don't have applecare support on these three and are interested in turning them in to two (hopefully) or one working model for a teacher.