does a rare color combo constitute a copo car

No, not likely. Special order colors were normally run thru Fleet & Special Order dept.
C.O.P.O. existed primarily to make batches of cars with equipment that was not part of a standard Chevrolet system. Chevelle taxi cabs, for an example. Air force vehicles - anything done usually in quantity w/ special equipment was programmed and scheduled thru the C.O.P.O system.
Don Yenko was the first to gain from this when he purchased 100 Corvair Corsas with certain special equipment that were further modified by Yenko Cheverolet into the Stinger. That opened the gate for other performance Chevrolets to be built with the involvement of Vince Piggins and Ed Cole.

Dan

I have a GM COPO catgalogue that lists all kinds of car and truck stuff. It doesn't even mention the COPO cars. It skips those numbers. I guess they weren't very important. ;)

From looking at Chevelle special paint build sheets for many years, it looks like some were done on a COPO, some on a F&SO, and some just on special order numbers.

Do you have the build sheet for this car?
What does it have for a paint code on the trim tag?

One Chevelle build sheet has "COPO/special paint" typed in the option field.

It should have something about the special paint on the build sheet and/or trim tag

here is a post with some examples
http://www.chevelles.com/forums/show...=289637&page=3