Originally Posted by Pro Alloy Motorsport

IIRC chasis number starting with BFAT ?stamped around one of the strut tops
anti tramp bars +brackets welded to the chassis rails, double top plates on the inner wing/strut tops - The early car up to '72? had battery in boot, remote servo and hydraulic clutch cylinder on the drivers side bulk head....

could be wrong though all from memory ( i had a Mex when I was 17!)