Replacing the clutch shoes couldn't hurt, but have you checked to see if the clutch springs are weak? Do you have the clutch shoes trailing?
Also the stingers being broken off the car will cause it to not tune right.
you say you keep leaning out the bottom end. If the top end is too rich it will cause you not to be able to lean out the bottom. The top end needle or (Main neelde) also controls the bottom end to a point. Remember that the 2 needles work together. If you change one the other will be effected as well. Just not as much as the one you made that change to. However the bottom needle could be your problem with having to adjust it in so far. IE: bent needle, worn out neelde seat.

The first thing I would do would to be replace the broken pipe. These pipes are tuned and the stinger has a lot to do with tuning.

I hope this helps.