Also, you mentioned going with a K20 because it is “newer”. Don’t think because B series are older that parts for them are hard to come by. There are so many parts for B series motors, but there are also a ton for K series as well.
You’re right, there is a lot of fab needed to fit a k series. It’s not thy the engine is newer, it’s more of the appeal of a newer ecu, and parts associated with the k series. Keeping the b and making sure it’s well done may e the way to go…