The inverters power the electro-luminescent strips on the gear selector, window switch, and mirror switch.
The Original Equipment Manufacturer (or one of) is still in business but I have not checked to see if replacements are available.
GM part numbers:
1642274 (black)
1642275 (pink)
The main difference between the two inverters is the input current, and the output frequency.
Contact:
Endicott Research Group, Inc.
2601 Wayne Street
Endicott, NY 13760
Phone: 800.215.5866
http://www.ergpower.com/