Thanks for the responses. The motor I had was really stuck and corroded. I managed to get the cylinder off, and the bottom end might still be okay. One of my biggest reasons or the swap is that I absolutely despise electric starters. I've heard all the arguments for them, and I can even agree with some, but I can't bring myself to start a motorcycle with a button (unless it's the only way. I know a lot of bikes don't have and can't be made to have a kicker). I am fundamentally and morally opposed to it. To use an electric starter when a kicker is available would be to tear apart the very fabric of who I am and all that I consider sacred, leaving me an empty, soulless shell of a man. I feel that strongly about it.
So my original plan was to source a parts motor with all the kick start parts and do the conversion to my existing E motor. I know that I'm going to have to split the cases on the E motor, but the '89 parts motor I found seems to have a good bottom end. It would be nice if I could get away with not splitting any cases. I'm not afraid to do it, but I have a lot of other projects and torn apart motors to deal with.
I don't want to get an earlier frame because the one I have has a clean title, is in very good condition, and well... I already have it.
Also, perhaps I was reading your replies wrong, but I think the problem is that the kick motor sprocket would be too far inboard on the bike. This means the sprocket would need to be moved out, not in like I think you're suggesting.
I might just end up splitting the cases and doing the kick conversion to the E motor. It just depends on how the parts motor looks when I get it and how hard it looks to line up the sprockets.