Love the suggestions! Never thought of the Cibies before... great idea as the rally style fogs and running lights are probably very similar.
I'd like to see an example of the fuel cap as I picked up a detail which will represent the surround with the holes in it well but hadn't decided how to handle the cap itself. I'm saving the original that came off along with the engine in case someone with an unmolested original MPC MantaRay might need it.
The body I believe is Lexan. Mine looks like they were having some kind of issue with the plastic as it has all kinds of little nicks in it on the underside. Here I am cutting, heating, and bending a piece of Lexan to fill in the huge cut outs that were on the underside of the body. Never tried this before, so that was fun. Picked up some tube glue from the local plastics supply store.
I got a little crazy with the chassis and I'm still not done. Here is a picture of some of the foolishness that went on there.
Lower A arms, upper arm with inboard spring and knuckles made out of brass connectors with 1/32 pins and holes.