I don't know if this fits as a project for here or not - honestly, I feel a bit embarrassed because I'd have been so much smarter building your working table since I cut everything out from the radiator to the side rails to the trunk floor pan... of course, I didn't do it all at once... it just kind of ended up being the way I've done it.

It was a stalled project (and still is on life-support because it took 3 years to get the wiring harness... weird, no one makes a wiring harness for a 2.8L V6 GM motor..heh)

It's a 1979 Fiat Spider 124

It has a twin-turbo Cadillac CTS motor (V6)

A couple shots of it

is what I started with - it cost $300 and it ran, drove, and stopped.... ish.

so here's the motor in place.  To get here, I replaced the entire front end with something similar to the Capris you have there in UK, also replaced the rear end as well

I built headers for it to put the turbos on and moved the firewall back 12" (30 cm)

replaced all the floors... I probably cut out the only non-rusted 124 floor in the entire world, though I made good money selling it online

6 speed transmission

so here's what it looks like now.... just like it did before but with nicer wheels

which is the entire point... 500 hp Fiat Spider that, outside of the 5 lug wheels, will look pretty much the same... oh, and no rear seat