FFR sells 10 times the kits any other manufacturer does. You will hear more good and bad about them for this reason. I have ridden in several FFR cars and ever since the mark 2 came out they are fantastic. The foot wells are much better quality than some of the other kits out there. The fiberglass is well done but like any glass part will require prep for a show quality job. Its has one of the best instruction sets out there. Has kick butt service if you get in a bind. And its hella cheap to boot. The mark 3 which will be released soon is setup for the modular motors without any kind of modifications. I like the factory fives as you can build them any way you want from drag to road race. There is 100 different ways to set the car up.
I would go for a bit of a mix of new and old if it was me. Modern brakes, tires, suspension, and a carbed engine. People will know its a kit no matter what unless they are morons. No need to try an pass it off as real. Build a car that you will enjoy and don’t worry how Shelby accurate it is. As long as the body looks right its fine with me. I don’t want all the quirks of the original car.
People get into authenticity but unless people are morons they will know it’s a kit. The odds of seeing a real cobra on the street are insane. Also people romanticize the original car. It was freaking awesome for its time but it had quirky handling, a flexy frame, the 427 style cars didn’t handle nearly as well and were never as successful as the 289 cars, the brakes faded like hell, the bodies were damaged easily, the steering was too quick, the interiors and foot wells were cramped and hot, the transmission was primitive compared to today’s units, and they weren’t reliable. So building an original a car as possible these days would mean building an inferior car.
Don’t let snobby people tell you that you need a concourse cobra. You want to drive this thing every day, have it be reliable, and perform well. A factory five cobra will do it much better than an exact nut and bolt 427sc copy. A properly built factory five or any kit for that matter will out perform an original 427sc in every category and be more pleasurable to drive.
Factory Five owners group with great discussion forums and build ups so you can get an idea. No other brand of cobra kit has so much info and people available to help you. http://www.ffrog.com/
Plus you could sell the shaker kit to someone on this site and make some of your money back. I would think you could just use a normal intake for these engines, but you would have to ask some of the Mach guys on this site, don't really know anything about them..