Never been in a forum before. Kind of cool unless I screw up...
Anyways, I have a 68 GTX. All original. I drive it whenever I need to go out. I built it many years ago. Interesting story. But I am now a grandfather (soon). Need to add a tether for rear seat restraint. Tether design, no problem. Attachment via: 1)bolt through package tray, 2) tether around rear seat into trunk and to spare tire carrier bracket or ????

If anyone has pondered this issue and came up with elegant design, let me know.

Thank you.

 

It's been a few years but the new carseats have a tether strap and one I bought had the bracket for arachment.
by a good seat....