I had a dump bed on my 52 which I have removed. I didn’t take to many pictures of it but here are a couple which may help. Basically the sub frame of the lift acts as support to the cross rails that the box sides and bed mount to. I still have the old dump frame behind my shop. I may have better pictures if you need more. As mentioned above, the frame tails do get cut off to allow for the bed to tip.
