I had several of the plastic adjusters that were stripped out.... and one was actually cracked as well.
Used zipties to fix...
On the cracked one I glued it back together and then put a ziptie around the perimeter for strength.
On the ones that were stripped out. I used the smallest little 3" zipties I could find. Run one ziptie down through the center... out the back... and then up to the front again. Tighten is down. The ziptie gives the screw a new surface to bite into... just like it was threaded. Now the screws fit tighter and adjust perfectly. Large zipties wont work because the are too thick.
Since I am dealing with 34yr old plastic, I went ahead and put zipties around all of the perimeters for strength... to hopefully prevent future issues.
Simple and takes only a few minutes to do.
'79 CJ7, stock 304v8, T150 3spd, Dana 30, AMC 20, Dana 20 T/C, Flowmaster 40 dual exhaust, 4"spring lift, 1-3/8"shackles, 35x12.50 Toyo A/T, 15x10 M/T Sidebitters, rear 1pc axles, Warn front bumper w/VR8000, custom 5" tube rear bumper, nerf bars, Tuffy (console, glove box, side rear speaker/storage boxes), new dash panel and Autometer gauges