Nope that wouldn't work, do that and you wont go anywhere at all. The factory diff's are "open" diffs so they send the power to whatever is slipping, seeing as their would be no half shafts (they're not axles) it would send all the power up front and you got nothing but some free revving action.
Modding the factory drivetrain to be RWD is not reliable, period. Or at least I have never seen or heard of it being done in a way that it was reliable. The rear diff and transfer case just aren't built to take 100% of the load, I think normally the rear diff basically "explodes". This means you have to pull the engine rotate it and do custom EVERYTHING if you want a reliable RWD DSM. Which is going to get $$$. There are however RWD kits of sorts I think, though they're more drag strip oriented. I know of at least 1 guy that makes trans adapter plates so that GM, Toyota and other transmissions can be coupled to the 4G63. You're also going to have to cut up the car and build a trans tunnel etc. etc.