Gustave, GET aggressive with a piece of coat hanger wire. Just route that out and keep working it until the GUSHER that happens when you break it loose. Work on it until it happens. No matter how long it takes.
Not sure if that will help with your overheating. Be sure you have a 180 degree T-stat with a 1/8" hole drilled in the side of it just for good measure.
Lean, check the mixture screw. Start by turning it all the way in, then backing it off 1-1/2 turns. Go from there.
