A.........build based on an ex-California 240Z integrated with a UK body shell and converted to RHD.
I wonder where the 50k has been spent?
The spec doesn't seem anything to write home about? I'd put £50 on you taking that to a specialist to get prepared properly would cost you ££££'s.
Even the pics show a corroded looking rear underside, might only be external components but it doesn't smell great for the effort thats gone into the rest of the car.
In 2014 the built cost for this was in excess of £50000 and if attempted today to the same exacting build quality and specification would be considerably more.