Thanks everybody for all the info about narrowing this 9' Ford rear I picked up to have installed in my roadster. I can't do this work myself so I'm sending it to a hot rod shop. I'm trying to do this right but as inexpensive as possible. It's a rat rod. We were going to keep the buggy spring ( Model A frame ) and maybe remove a few leaves because this car is so light. Install the narrowed rear with the "pumpkin" centered and probably use the aftermarket shocks that are on there now. What I don't understand is ladder bars and/or 4 link suspension. I understand their purpose but since they are rigid with a towards the front of the car pivot point how does the rear end manage to go straight up and down when you heat a bump. It would seem to me that the rear end would want to go up and down in an arc or part of a circle that has as its center or pivot point at the front of the ladder bar or other what ever set up you put on there? What am I not understanding?