Just found this post from looonng ago while searching for info on the rubber bumper 71 Plymouth jack hook. I have two of the rubber bumper hooks. Both are grey and only have the pentastar stamped in them no part numbers...I can post pics over the weekend if anyone is interested seeing in them. I also have a green Canadian hook that has the part number and pentastar stamped on the face which is unusual as most have it on the inside...