First off, making it 4-door only is ridiculous. Secondly, no reason to not offer it with lower trim models - a Sport with the V8 option, or a 2 door Rubicon with the option.If you were in charge for a day, what would you make the MSRP and how did you get to that price?
Then, all you do is add whatever the difference is. Absolutely no reason they couldn't offer a V8 at 35-40k.