I have a 1998 Kia Besta 2.2L van.. unfortunately, engine is going south.. what are my choices of engine? I called wilcor and they gave me the following:

1) same engine 2.2L (RF engine perhaps?)
2) RF Turbo Diesel
3) R2 engine (2008) release

the 3 choices does not require any changing of mounts and will make use of my existing transmission while:

4) 2.7L engine

would require change mounts, subframe, and tranny.

What do you think would be cost effective?