If I seperate the ignition coil module ('95 LT1) from the bracket that the coil is on (but leave it ICM on the heatsink), can I relocate it to maybe say under the corvette fuel rail covers? I have to relocate the coil/icm anyway for my setup, I just don't know if this will cause any overheating problems for it.

Also, where can I get just one spark plug wire? (The #1 wire will work...)

 

As long as you can make the wires work put it anywhere! The further form any heat the better. You should be able to get a single wire / coil wire at any decent parts store. If you have one that works take it with you and ask whomever to match it.