So, as my post below states, I have a 91 mr2 here that has a spare engine and 3sgte I'm building.

The 3sge has top feed injectors, oil cooler, larger throttle body, larger duration cams and side feed plenum/intake.

Should I just swap the head ? Seems benifical? Has anyone bothered?

Which gen na head? To be honest, there's nothing particularly beneficial of the gen2 3sgte head over the na head, and gen3 3sgte/ge heads are essentially the same with different cams/inlet manifolds etc.

Throttle bodies are the same size for eaxmch gen regardless of turbo or NA. Gen2 is 55, gen3 is 60.

Intake port holes are smaller.