Marcos Maniacs

Does anyone out there know the source Marcos used for the wiring 
harness for early steel-chassis cars? Mine is a '69 or '70 (Rory has 
not ever been able to track the actual serial number). Many items 
were "borrowed" from the Spitfire/GT6 Triumphs. Any ideas about the 
wiring harness? The Roadster Factory (in Armagh,Pennsylvania) has a 
sale on Triumph harnesses for the above mentioned cars of the same 
vintage as my Marcos. When I convert from right-hand to left-hand 
drive, a fresh harness would be nice.  Thanks! - Donny Lang