Re: LS1 Front Brakes on rear end
Shouldn't be a problem, but you might need custom brackets.
You will need a brake proportioning valve, but you should have one with rear disks anyways. The volume needed to move the pistons is more, but then so do wheel cylinders.
Mostly its not done as its just overkill. Why spend the money for big huge disks, big calipers, etc when the rear brakes do so little compared to the front. Better to spend the money on the front. But you already have them, so its not like your spending anything, so why not.