I need help figuring out where I can get the rubber bump stops for the upper & lower control arms off the front end of my '68 Buick Riv. I hadn't planned on replacing them, but one of the lower ones was just about broken off, so I need a set of lowers for sure. The local NAPA had some for a '71 Riv, but they attach w/ a bolt, while mine just pull a smaller wedge of rubber through a slot in the control arm. Any great ideas/sources out there? Thanks!