GM (parent company of Chevrolet) make so many makes and models, you would think they would have standardized the. Why The Two-Step Paint System Your 2004 GMC All Models is painted at the factory with a high quality basecoat/clearcoat system. Resin quality, solvent viscosity, pigment colors and toners, vehicle age, and regional differences all play a role in a vehicle’s paint coloring. Matching the exact auto paint color of your Chevrolet, Buick, GMC or Cadillac vehicle can be a frustrating endeavor.
In that case the truck may not be victory red, but to make a long story short, even if the door is victory red, the paint is still not going to match well enough, not be very very noticeable, even with it being the same paint code. Plus, their paint code format is confusing. Show your true colors with GM auto Touch-Up Paint. SInce you did find the code on your truck, I'll assume you are looking in the right location, and another possibility would be is the truck a real xtreme, or one someone bought the kit for, painted it and put it on an s10. My guess would be you're probably not looking at the paint code number, if you are just looking at the door itself, since they are in the glove box of an s-10.
I've never came across a paint code on a chevy similar to a 64d, the ones I've seen have always been u with some numbers following it, like u9260. In 99, xtreme's were still only available in 3 colors, white, black, and victory red, so if the door is off of a 1999 Xtreme, then the door is victory red. 9260 is the code for victory red, and depending on the year there are always a few variances, but they'll still be 9260 with a letter after them.