Here's an update to the progress on my 500 build. As you can see it's coming along quite nicely. I installed the carbs after boiling the rubber boots in wintergreen oil and water. It really did help with the pliability. But for those whose masculinity is challenged by the aromatherapy you exude at every red light- other paths may be taken.
In order to get the carbs, boots, and airbox in the frame I found that if you have everything set in the frame before installing any of it, you'll have better luck. I went from front to back- first boots, then carbs, then the airbox boot, then the airbox. It was a cold night when I did it so I did keep the rubber flexible with a heat gun. It worked out well. I'm very pleased that I used the stock airbox and not some other aspiration system.
I strapped on the mini turn signals that I ordered- I was a little nervous that their quality wouldn't be good. I ordered them pretty cheap ($22 a pair) from a Chinese ebay vendor, but they ended up being real nice. All powder-coated metal and LED, with amber, clear, and smoke lenses to choose from. The double tail light- not so much. Cheap "chromed" plastic. It looked better after I painted it, but I'm considering looking at other options.
One problem may be the cables I got for the bike. I didn't consider how much the cafe bars would shorten the distance the cables had to span. Problem with the 500 is the unique way the clutch cable attaches to the motor case. I'm wondering if I can shorten the cable I have somehow.
Now it's on to the exhaust, which I've ordered (MAC 4 into 1), the brakes (rebuild front), and the electrical. I have a lot of wiring work still to do. I guess I'll need tires too, or else there will be some sparks.