[DavidG]

Couldn't you just shorten and add threads to the bolt? Apart from that and far more importantly, only the very top leaf of an original spring is relieved along its upper outer edges to compensate for the fact that there is a small radius to the top inside corners of the rear cross member (it is not a 90 degree corner). What you are suggesting would leave only the edges of the remaining top leaf in contact with the underside of the cross member which is well removed from the design intent.