My Cali’ 3’s side panels had damage around the mounting holes. One of them had a chunk of plastic missing that was about the same size as the hole for fitting the mounting screw. so in effect the clearance hole had become an open ended slot. The other panel was cracked aroubd the hole, and the plastic was about to fall off.
I used cable ties cut to length & trimmed to width for a good fit, I used superglue to err, glue them together. I was surprised that it worked, but, it does.
Don’t know if the plastic on other models is made from the same material, but, worth a try if yours are in a bad way. I did this quite a while ago, so it’s stood the test of time.