I saw a 2f motor with 4 speed tranny (no trans case) and was wondering if that is a direct swap for the 1f in my 72. Mine runs okay, but a little sluggish going up the hills around the area at highway speeds. What are some of the differences in the mounting of these 2 engines. Is it as easy as pulling out the 1f and bolting in the 2f? My 72 already has the floor mounted 3 speed...