No room for new throttle shaft bushing

That muggy weld crap works great.. on aluminum cans and radiators. Guys at the show always use this stuff on the lightest stuff around. Try using them on anything with some mass, like a slanty intake or this part (well maybe). you need LOTS of heat to get the entire part hot enough to melt the stick with just a touch on it. Id try and use a oxy/acetylene rig if you have one or MAPP. Propane wont get it hoe enough IMHO. I tried to braze an aluminum crack in a slants choke stove and I rested the propane torch directly under that crack for probably 7-10 minutes and all the stuff did was ball up like solder. Even tried using acid flux on it and waiting for it to turn 'root beer brown" as directed but it never flowed. I gave up, drilled it and stitch pinned it. Also as stated if you drill out the hole to bushing OD, it has to be jigged to get it dead nuts centered in the original bore or else the butterflys wont go on right at the least. I heard a guy do this with an egg shaped throttle bore: coat the (new if old one is damaged) shaft with silicon spray lube and then install it with the butterflys all seated in their bores. Now pack the JB weld in the slightly opened up bore and let it set up. It should not adhere to the silicon spray so your shaft should break free easily once the JB is fully cured. Give it 48 hours. If that scares you, drill out the elongated bore oversize of the bushing and do the same thing: install the bushing on the shaft and set the JB around the centered bushing. It should seat and make the bushing the new bearing.