Sounds like you have a great plan for it.

If it turns out not to be a real Manx, which I doubt, I'm interested.

This thread lit a fire under my but to go talk to the guy here about the buggy I saw and turns out he still has it and it's a Sidewinder made by Autocraft, they were kinda styled like the corvette. It needs a lot of work and he's saving it for his 12yr old son. So I'm SOL.
Looking forward to seeing yours on the road.