Danny - This does sound like a great idea and I hope it all works out for you.
I assume you can also get a bit of money back selling off the bits from both cars you don't need.
Good luck, Paul.
PS
I've seen a few clever combinations of old body shells on modern running gear on "Rods & Sods".
E.g. This 1948 Chevy pick up.
Actually has a Mazda truck underneath.
Build thread here:
http://www.rodsnsods.co.uk/forum/gar...da-b2200-45080