Tell us what is YOUR top 10 most important points as related to owning a GT40.
So as to help I let you in on mine.
1. Buget
2. Must be appear to be a real GT40 as far as actual shape and dimention.
3. Same basic chassis configuation as the real car.
4. Performance, near equal performance as a real MK1 car. Power, ballance, and overall grip. More or less 5ish to 1 power to weight ratio, proper gearing, and good modern tires. 2500 lbs, 400hp at the crank, and 17in Z rated modern summer max performance tires will de it.
5. Self build kit. 5 is closely related to 1
6. Suport, help nearby from others with like manufacture or good remote suport via phone, email.
7. Gearbox acceptance, what types will the chassis in mind accept.
8. Body fit and gaps. This can be a very big deal for a guy who settes on a self build to perserve buget. Some of the new cars are near perfect in this reguard. Some of the older types can be up to 25% of the build effort in my opinion.
9. Ability to purchase less than a full package. Or better yet the ability to upgrade or delete systems, equipment. A good example of this would be brakes on a track only car.
10. Shipping costs if overseas and all that is related to a out of country suppler.
BIG NOTE: you need to learn about all the ins and outs of gearbox choice. The gearbox is the center of the entire project. It will determine many future choices for you. Better to spend more on the gearbox and less on the motor than via/v.
Put together a list of your own and go from there.
Buy the way, this part can really be fun. Kinda like sitting at the bar, looking them all over and picking one to dance. You have to decide what you want.