Thanks guys! I'm stoked to have this in my collection. The only two known, but I might be the only person who gives a crap...
After looking at it a little closer, I see the engine area is trimmed a little higher than in the box art.

sucks... correcting that to back pour a mold will not be fun. I'll have to leave extra material there, and then carefully shape it down to make the mold correct.
I could try to back pour the body from the NIB kit, but I hate to risk screwing it up. I'm very comfortable with many materials and processes, but would hate to risk damaging what is probably the last original unused version of that body on earth.

Plus, these bodies are whatever weird plastic they used that predates lexan's appearance in the R/C industry.