those t-bird turbos are setup for a 2.3 liter. so 2 would be good for a 4.6 liter. a little small. but they will make boost quickly. max out about 8 psi and 5,000 rpms.
the 300zx first generation turbos have t3's and are setup for a 3 liter. I see lots of them at junk yards. 50.00 each.