Thanks for all the replies. Interesting point about suspension, I hadn't thought about that one. Colin I agree with the MOT point, like many I can't understand the Government's stance on no MOTs on classics. Personally I'd have an MOT done just for a second opinion and to be honest pride of having car that would whistle through an MOT. Dave I've had a look on the web regarding the exemption from tax for historical vehicles, can't see anything that would make a car not tax exempt because of a different engine but certainly one worth considering.