The '68 bumper jack is specific to that year only because of the style/make of the bumper,a LeMans and Tempest jack would also be the same!Check for any Swap Meets,GTO Shows or the yearly POCI (Pontiac Oakland Club International) Meet each year for a good used bumper jack?You can also check the for sale section at
www.performanceyears.com or
www.classicalpontiac.com and find one for sale!