Rearend Question

[TimE]

I was wondering if anyone knew what the width difference is between a stock rearend and one out of a late model Silverado(99-up)? I was just contemplating the possibilies of having rear disc brakes and remember someone on here(I think it was this board) having installed one in there truck.

Just curious if it would actually be worth pursuing or if it would be too wide, to the point of really limiting rear wheel choices.