GMCdp,
I can't take any credit for this info other than I was interested and did some searching. As your rig seems to be a GMC, I went to their site and dug around.
This is what I think I discovered. The 'cr' you are searching for isn't a color, but a tracer in a 'X angle'...a 'cross tracer' hence the 'cr'.
A hypothetical wire color would be; Nat.blk cr tr. This would translate to a natural color wire with a black cross tracer.
Does this sound like it might be the straight skinny. Take a look at the GMC site and I have enclosed a link that's interesting too.
http://www.riwire.com/Catalogs/sup/pages/wire.htmStuart
