Way back, while working on the motor mounts, I discovered that the choke boss on my rear carb body was broken, preventing the choke from operating properly (or at all). At the time, I fixed it with JB weld and a scrap of aluminum, but I'm sad to say that the fix failed. (I'm not necessarily blaming JB Weld, but I haven't had much luck using it in applications involving shear, torsion, bending... well, any kind of stress at all, really.)
Although the idea of drilling holes in my carbs left me with a pit in my stomach, I figured- short of welding- using mechanical fasteners was going to be the only thing strong enough to provide a lasting fix.
broken choke boss
I started by filing the broken remnant of the boss to create an even mating surface for the repair piece.
Next, I "machined" a repair from some aluminum scrap (using a hacksaw and a file), then drilled and countersank it for a miniature machine screw to fix it to the carb body. Finally, using utmost care (and holding my breath the whole time) I drilled the remnant of the choke boss on the carb body and tapped the hole.
repair screwed into carb body
The car starts a lot easier now!