Thank you, King. Is that the WT-540 carb? Your job looks good to me.

I'm not sure when my G-38 was manufactured, but I did find that it has the aluminum prop shaft, and the WTA6A carb w/no choke.

I found a useful article, both in terms of carb replacement and ignition conversion. Looks like the WT-540 is a bolt-on fit:

http://tech.flygsw.org/g38ignition.htm

The WT-540 is the way I wanna go, as I like the auto choke shutoff and large bore.