[68bird400HO]

Here is a picture of the mechanism that I believe is correct for the trapazoid style jack for the second gen firebirds. It looks a lot like the first picture in David's previous post but look at the angle of the pin and the pad (circled area). Also see the dotted line. The angle of the pad surface hits the stick about an inch above the top of the unit. If you look at the first one in David's post the angle isn't that sharp.

The mechanism on Scott's and Den's Y jacks I am sure are correct for those. The pin-pad angle looks the same as on the trapazoid mechanism pictured below.