Can a 3B IP work on a B engine? My IP on my B is leaking and and I have a 3B w/ in-line pump sitting in the garage that will eventually replace the B when it’s time. I would rather spend the money to rebuild the pump from the 3B if possible. If not interchangeable I’ll rebuild the B IP as I am not ready to swap engines yet as I feel the B has a few more miles left in it.