well those are both RWD
the LS4 thing jeeves suggested MIGHT work, but i still think its gonna be a LOT of custom work and cost a LOT of money. in all honesty, if this is something you think you can do in a few months for $XXXX, then dont even bother. anything like that is gonna be a project thats gonna take you at least a year and cost you a shitload of money. its one of those deals where if you win the lottery and cant think of anything else to spend your money on, then pay someone else to do it and it it would be something nice to have.
im not trying to talk you out of it, but i just think you really need to think about how much is actually going to be involved in doing something like this. you said the above ones were the only 2 that you knew of, so think about it: if it was easy to do, then wouldn’t you think there would be more than 2 of them?