What is the thinking here? Is it on one hand " I've just reshelled my MX5/Sierra" and on the other " I've just built a new car" with all that that implies...
Not really such a clear-cut difference. You are building a car around a different chassis in both cases so effectively it's the same thing and both should end up registered afresh as a Westfield. When it comes to registration of the car, though, there are 3 possibilities:
1) You build a car with all new parts, and can prove their "newness". You'll get a new age-related plate just like any other new car.
2) You build a car using parts substantially from a single donor, and have the documents for the donor to prove it. You'll get an age-related plate of the year of the donor vehicle (sometimes they'll even let you take the donor's reg. no.).
3) You build a car using a mixed bag of new and used parts of various ages, or can't prove the age of all parts. You get a Q plate.
There are advantages with a Q plate in some respects in that you can get away with more than an age related vehicle at MOT. You can't transfer the number plate if you want a cherished plate, etc. though, and there is a little snobbery against them among some.
Also worth bearing in mind that the emissions testing criteria are based on the engine age so to avoid having to have a cat you need a pre-august 1995 engine with proof of age from memory.
That puts you into the MX5/Zetec/C20XE/Rover V8 territory. Maybe an early X30XE?
Of course, if you fuel inject it, having to have a cat is not a massive problem, but if fitting carbs it is. Also, there's no reason why you can't fit a newer engine once it's registered so you don't necessarily need a mint pre-95 engine. Just one that runs.
I personally would prefer to go down the BIY route rather than a factory fresh one, purely for the satisfaction of doing it.
Fair enough. That was my take, too.
Plenty of food for thought here, space will be the single biggest constraint I think.
I built mine in a single garage with no problems at all They are small, especially before the bodywork, wheels and tyres are fitted.
I would try to see a few in the flesh, as that will give you a clearer view of the path that's right for you. Hoping mine will be back on the road soonish in which case it'll be along to a few meets. Failing that there are plenty of clubs who probably meet locally to you. Westfield Sports Car Club in particular springs to mind.
http://www.wscc.co.uk/local.htm. I know there's a regular meet at Forest Green. Probably a few in Sussex too. Go along, kick some tyres, talk some bolax and blag a few rides...