Thanks for the input folks. My C4.2 was a fantastic buy. Few niggles now in only a short space of time - diff needs attention so a gear diff would be handy.
I found a Cobra B42 conversion but it seems more compatible with the B5M front end but was wondering if I could get the B5 chassis parts and used some B4 parts and have two 2WD cars to play with.
I'mm keep plugging away as I like a project