Hi jclay,
Had a similar problem with my 97' CC 3500. The dash lighting was going haywire when I had turned on the ignition. It turned out that it had too much juice (wrong fuse put in) going to the trailer brakes and melted some of the wiring to the point that pos/neg wires crossed. Dash lights flashed, door chime going crazy, etc. I don't know if this helps but... Did you make any changes in wiring or fuses?
DP Member 9428<br />2002 Chevy 2500HD LT, D/A, Ext. Cab, SB, Dark Carmine Red/Med. Grey.