On the site where oko94 found the answer it says about this car:
1) That the serial tag calls it a "BBG Custom"
2) Here is what a poster has written:
QUOTE
The Car is all steel, rear body panel, front end, doors, hood, trunk, checked all with a Magnet
I believe the body is a real TR3 Modified
the rear body panel looks like a TVR 400
the car is sitting on a Daimler SP250 Frame and the Daimler SP250 v8 Engine
I am now looking for Information on who built the car
if anyone knows any history please let us know
the car came out of New York
UNQUOTE
I don't know if that get us any further towards finding out who built this car!