The radiator ended up in the spare tire well, like it was made for it! I picked up a nice Griffin that was a perfect fit, right down to the outlet/inlet placement.
That engine is a 4.1 V6, It came out of a Caddy, but it was mainly installed in the Buick Riviera. It's a basic off shoot of the 3.8/231 that was in everything during the 80s'.
The engine has aluminum valve covers, timing cover, water pump, intake, and tube headers. Small 390 carb and aluminum air cleaner and throttle brackes and such. It comes in around 100 pounds heavier than a loaded stock VW mill. The water weight in the radiator and the fiberglass rear deck lid, plus the rear sheetmetal that was removed pretty much balances everything out, front to rear. We placed jackstands at the car's mid-point to check and it really was no more tail heavy than it was when stock.
All of this to say, grab that Kennedy adapter and stuff something in ! ! ! !
Luck,
TC