Your plan should work just fine!
Take all longitudinal parts from the Quantum engine: mounts, oilpan, etc. It will fit like a glove!
Things to worry about:
-Placing the alternator. you need longitudinal-diesel mounts for this!
-The oilfilter. It is positioned diagonal in your Q for the clutch cable. But the mount won't fit your 1Z, it's too small. You need a mount from an audi80 TD/TDI. Or really work on the Q mount.
The crank has a hole to fit the bearing!
You should take the fuelpump out, and flush the tank. nothing else.
Homemade downpipe, or again, Audi80 TD/TDI
Should work out if you got the parts. I am builing a Q TDI too (in Holland).