swap R56 engine into R50?
 

just wondering if my R50's CVT would go well with the new peugeot engine in the R56. not planning on swapping for a long time, even if it would be worth it. because 40 miles per gallon is amazing on one hand, but the R56 looks bloated on the other hand (no offense to R56 owners). plus another car in the family might only have a few months left on its engine, and i want to see what a mini engine can do in a lincoln, so i already have a use for my R50's block if i pull it out.
(yes, i know, i'm an irrational thinker...muahahaha)

also, if it's a worthwhile mod, any ideas other than ebay where i can find just the block without an entire car?

The dealer won't even sell you a block minus internals so Ebay is probably it. I have no idea how the CVT will act with the R56 motor attached. If it will even bolt up the same. If it works and you can fool the ECU into liking it (not easy or cost effective if possible) it would probably be a good combo. The CVT is always keeping the motor in the powerband so the car should always be right there for making power. Good luck is all I have to say.