Definately the easiest and most practical 3RZ to use in a conversion is the T100 2WD 5spd one. Not only is it a 5spd and you will have the correct flywheel and clutch, but its also the most basic in terms of smog related equipment that the computer needs in order to run correctly.
My 3RZ came out of a 1995 2WD 5spd T100. Marlin's 3RZ also came out of a T100, but it was a 2WD Automatic. He bought a 5spd computer that only required the relocation of a couple pins at the ECU plugs to run.
The years you are looking for are all T100 4cylinder models from 1995-1997.
My engine had 140k, Marlin's had 80k, both of our run like they've got 5k.
Mike