Nice! I'm happy with the .50 on mine - no chamber to deal with, and it matches other guns I have, so it keeps me from adding yet another bore size to my collection (.36, .45, .50, .58, 1.5...). He's looking good! Make sure you square up the butt end, so the shaft will fit well. I had to do a bit of that on #1.
Looking forward to some family photos, Dan!