I have never seen a spec. but I guess you could go to the other end and measure the travel of the control cable. That would tell you how much travel would be needed at the control end.
I would start with connections on the radio, corrosion..etc. Antenna is the most likely culprit, not the radio. Buy a good antenna not an amazon special. Antenna is the magic that makes radios work well.
I use Epoxy for all my work. US Composites is my source. Good luck, it is usually more work than expected and will use much more materials than you expect.
Yep, wetsand, by hand. The Harbor freight buffers are pretty good these days. They have a good assortment of pads and actually sell good compounds. You tube has some good wetsand vids and buffing stuff.
I have found that with older controls there is sometimes enough wear in all the parts to reduce the travel. Not one part is actually worn to the point of falling apart, just collective slop. I have stopped fixing older controls, teleflex aftermarket controls are what I go to these days.
