The reason that most people run the toy rears up front, is that the center pin is offset toward the front. It's about the same measurement as the stock front, but the longer leaf overall is more flexible. The Chevy springs center pin (IIRC) is more toward the center of the length of the leaf, plus,they do not have the military wrap on the second leaf. Most people will "hybrid" a leaf pack, mixing in other lengths and/or swapping leafs to gain lift and maintain flex.
