Report Part 1: Tried running without air cleaner, same result. I checked that I could breathe through it when blocking the wing-nut hole, and reverse-blew it with compressed air anyway.
The extra replies and suggestions have turned up overnight as well, so thanks all for that info, I will look into those things and reply with a "report part 2" once I get through that. In the meantime I grabbed a couple more photos around the carb, have attached them here, let me know if any problems happen to be obvious to those with an experienced eye...You'll notice that the original throttle control arm has snapped off, a piece of wire has been substituted and works great, a cheap solution...
