That makes it a lot easier. I would go with the DIY 52" spring conversion to get a better ride and more flex done with more common springs.
http://diy4x.com/product.php?product...cat=250&page=1
If both trucks are auto that will make things a bit easier, the front axle and drive train should work with the right cross members. The rear axle will work with a relocation of the spring perches and shock mounts. Not sure if the rear spring hangers are in the same location in a rear leaf C20 compared to a K20 so more research will have to be done as far as lift is concerned.