No need need for a tunnel for the exhaust. I was trying to think what else would go back there. I guess any lines for the brakes and thats really all I can think of. I like what Barrelsnbeer is thinking although the goal is weight savings. I dont think adding all that crap (though I like AWD idea) is gonna help that goal!
it could still be lightweight, just going through all this work to put an FS back in would be rediculous at this point (if it were me) there would be a sr20det and new rwd subframe getting dropped in. then smooth floor and light weight goodies. but thats my dream, lets see where tamn takes this