I know exactly what I would do. I would cut the barrel to 3", round butt the grip frame, refinish and add wood combat grips to the round frame. You'd have an excellent, packable gun. I have a Lew Horton 3" 629 and love the ergonomics, balance, and size. A .45acp in that configuration would be very neat.

Nice job on mating that mushroom head. That is one of my favorite features of the older guns. Also, before bluing you'll need to reshape the front sight slightly to get it to hit POA at your desired distance. You can choose your preferred load, shape it to the right height, then have it totally dialed in.