I broke a lever on mine while trying to pull off one of the knobs. The lever (slide) broke even with the face of the unit not allowing a new knob to go back on. I tried many different ways to glue it back on to no avail.
I ended up buying another unit (used) that wasn't broken.
I believe the parts houses (Rick's, Ground Up, etc.) sell them used (when available) and there may be a repro item now.
'69 Z11 Pace Car, 350/4 speed, manual top, console w/gauges, tilt rosewood wheel, AM radio