
Seriously though, I don't giggle very much while I'm doing this. It's just an expression.
The obvious candidates are the ones that have a bad, or old and faded dye job, and the parts can't really be used for a proper restore. I had two of these handy, and decided to see what I could do with them...this 10LS and a 10T (another post)...
The chassis is discolored on top, and the bottom has some fairly good scratches, but no real damage, so it's still plenty sturdy for running. The dye job I doubt was pretty when new, and had faded to a nice shade of BLEH.
The original:
Chassis stripped down before cleaning and a bit of buffing
The only things I really needed to replace were some hardware bits...a few stripped or rusty screws, the two big dampner washers, and the locking collar - which I already had in my spares, so no money spent (always a plus). Unfortunately, I didn't think to toss those washers and collar into the dye bath with the rest of the parts, it can wait till the next time I get that color boilin'.

So I threw all the non-black parts in the dye bath (some just to see what would happen, like the fiberglass T and the servo saver - didn't expect much from those, and I wasn't let down). I had read in various places that the plain RIT dye "ain't what it used to be", but that's what I had handy, and after all, this rebuild was part experiment, so that's what I used, the Rit Navy Blue.
I left everything in the bath for 5 or 6 minutes, then checked...everything was DARK...a good bit darker than I planned on making it. I like the color, but was VERY surprised how fast it worked.