macdave06
+1y
for wiring you can go to LT1wiring.com which is where I had mine done. they tune the computer and can set your gear ratio, tire size, transmission etc. They cut out the unnecessary wiring, relays and such, and label all open wires for a standalone harness. I believe on mine there are 10 or so wires that have to be tied in (gauges, starter, main power, fuel pump, fans, etc.). They can remove or retain emissions, pretty much anything you'd need done to the wiring. It cost me a total of 425, 375 for the harness work and 50 for the programming. I believe its only 325 or 350 to do a camaro harness.
Another thing I never thought about is that you may be able to adapt an r series transmission out of a turbo supra and possibly still fit in the transmission tunnel. I can't say I know much about the supra transmission other than I've been told its the same one that's in 5 speed jeeps and dakotas
Also on the heads I believe the iron heads outflow the aluminum heads, but the aluminum heads run a higher compression ratio. Which way you go depends on how you're gonna do the motor though.