Hi E-solver,
for the RX7 we're doing, my aim was to keep the motor as low and back as far as possible. That way the weight distribution would be closer to the 50:50. I recall from another thread in here that with a 2 piece driveshaft you need about 8 degrees of angle between the two pieces otherwise the hanger bearing floats or something, but it doesn't matter too much for the 7 because it will only have a 1 piece drive shaft. So for me, the gearbox crossmember is set to keep the gearbox level. It doesn't matter that it may sit quite low, as teh sump, sump guard, and exhaust will all sit lower.
By the way, I'm guessing that your supra was at the AutoSalon yesterday at the NZEFI stand, correct? She will be a beauty when she's finished.
Muzz