Hi Harry

I think the loop on the spring fits over a pin that is pressed into the casting. At least, that is how mine was set up, but my frame was pretty abused. I found the attached photo somewhere on the internet some time ago which also shows a plain pin sticking out of the casting.

It doesn't seem like a very secure way to install it, but I assume the spring tension is supposed to keep it in place.

Dave

Thanks Dave and Tim!  Dave, the only picture I could find was in Moen's IPE frame pictures, but it's too small to tell if it's a screw or what!  So thanks for digging that up!  Roll pin sounds a lot easier to get out than a broken off screw!