Update:
For those of you that don't read the 1JZ/2JZ section, I fragged my 1JZ not too long ago. With that said, I've found a lot of things wrong with the 1JZ.
The #1 piston had next to no compression. When I pulled the head off, it looked pretty good and there wasn't any scaring on the cylinder walls. Strange.
As I pulled the harmonic balancer today, I found a hole in the lower timing belt cover. The HB had caused the hole by rubbing it. It looks like crank walk.
Also, the timing belt tensioner wasn't being a tensioner. At All. The shaft was fully retracted, not even touching the tensioner wheel.
Something bad happened, but I haven't determined exactly what happened first to cause the other things to happen. I guess it doesn't really matter, there will be nothing at all from the 1JZ that will be transfered to the 1.5JZ except the manifolds. Everything else will be new.