Hey Jeff, I would put the 56s in AS IS and see if you like it. Not sure how well they'll flex but I can tell you what I've done to mine.
In your picture. Start at the leaf with the brackets attached to it. I removed the two leafs above that one. These two are the closest in length, so I figured I'd start by taking those two out. ( I don't know why, just did) Well, the truck looks great but the springs are close to flat and the truck is REALLY soft. I don't think they would hold up your Sub. I'm not sure which leaf to put back in the pack, but one of them will. It's too soft for a "do it all" truck.
In your picture. Start at the leaf with the brackets attached to it. I removed the two leafs above that one. These two are the closest in length, so I figured I'd start by taking those two out. ( I don't know why, just did) Well, the truck looks great but the springs are close to flat and the truck is REALLY soft. I don't think they would hold up your Sub. I'm not sure which leaf to put back in the pack, but one of them will. It's too soft for a "do it all" truck.



