A few days ago, I moved a side cover from a donor instrument to my extender (which had one cover missing). I found it a delicate process. The plastic seemed to be dangerously brittle; but, I got it moved without damage. As I recollect, one edge WAS slightly different and I took this into account when prying off and installing. So far, it seems OK ; but I haven't tried the extender yet.
My backup plan was to fabricate a part from 0.040" and/or 0.062" FR4, using epoxy for fabrication and a milling machine, with a fine carbide cutter, for coutouring. I haven't needed to do this; but it should work.
Stephen Menasian