the 16GB touch has two flash chips, presumably 8GB each. I'm not sure on the 8GB model.even if this were possible, how would you get the OS onto it?
Full Restore would do it - it clears everything down and starts again. I think there would be far greater problems to worry about than this though - you'd need pin compatible chips and some way of desoldering and resoldering Surface Mount chips. An investment of $100K or so should set you up so you could do iteven if this were possible, how would you get the OS onto it?