Well, I was 50% successful, lol. I used my test light and multimeter to test the harness where the stock Mikuni plugged in to, and low and behold, there were only two plugs that had any power when the key was turned on, and neither of them was where I had the electric choke wire for the Weber. If you point the plug towards the engine, the two spots that had power were the two on the far right, upper row. I had the Weber choke wired into a plug on the lower row, second from the left.

As I said, the choke wire on the Mikuni appeared to be red/silver, but that connection on the harness does not have power. I looked at a writeup someone did on swapping an SQ engine into a D50 (more or less same as the Monty), and it looked like there were at least two sources in the harness that should have juice when the key is turned.

So I used my test light and found two in the harness that lit up when the key was turned, and confirmed this by using the multimeter. I plugged in the Weber electric choke wire into one of these plugs (far right, upper row), and now that arm engages the cam thing I talked about earlier.

However, the "rattling" sound hasn't gone away, so it looks like I'll have to pull the air cleaner off and see what's going on with those butterfly plates at startup. Another thing I noticed is now that the choke is apparently working, it's a little harder to start and hold an idle. But as before, once the rattling noise goes away in a couple of minutes, it settles into an idle right around 800 rpms, and seems to be working fine, like before.

I'll have to put a few more miles on it, now that the Weber electric choke is powered, and see if I notice any difference, either in driveability or mpg. I'll post any updates as needed. I still think buying this Weber was more than worth it, because of the results I got in driveability and mpg. I just hope I don't get back to CA any time soon, because I'm almost certain that it won't pass smog. But for now, I'll enjoy the heck out of driving it here in the smog-test free great commonwealth of southeast VA, lol...