To each his own and if a G24 is what you like, it's your car and your money and I say go for it. I've seen some nicely done G24's so I'm not going to knock them. I personally have a G28 which I liked over the G24 but now that the Watson bodies are out there, they make the G28's look "second fiddle" and people are starting to look down their noses at the G28's. As I've said before, you are building this car for you and you are the person that must be happy with it.
Now with that said, I for one will enjoy reading your build thread and I'm in that camp of members who have serious doubt that $12K will build a decent car... but hey... prove us wrong and even if it comes to $15K, that's still an accomplishment. Unlike the claims we've seen of some new inexperienced member (without tools, a donor or any money) building some awesome front engined Firebird or Camaro based Lambo for $12K, you'll actually have a good chance of completing a car and the big question will be what the final total was and how you did it.
I will warn you up front that anything dealing with sacrificing safety will almost certainly create some negative compliments. I would never build a replica to the "Jackie standard" and telling builders to leave out things like hood latches and or opening panels with "a string" is just wrong for the hobby and even more wrong for those riding inside these things. Also if Jackie is trying to buy some publicity and give you a body and other parts to offset the total cost, this isn't really the "average Joe" building a car for under $12K and that's just playing with "loaded dice" if you ask me.
Best of luck and I look forward to reading your build thread.
Chris