I understand the 300zx being your dream car, or admiring the car as much as you do. If you plan on keeping the car forever, I say go for it.

But for resale value's sake, why not got with an FD RX-7. You could also probably get it to weigh much lighter. Unless money is a factor, which it typically always is, I can see why you'd go with the 300zx.

I don't know much about the 300zx but the aftermarket for the RX-7 seems to be pretty unlimited. I've always loved the RX-7 and would love to do one of these swaps.

+1 for going with a different chassis.

Are you 100% decided on going through with it?