Second ad Third Row Shoulder Mounts?

[64Bezer]

I have a 72 Suburban. It has front shoulder belts for the driver and passenger. The center front passenger and all second and third row seats are lap belts. My youngest is getting ready to move to a booster seat. Of course, you can't run a booster seat with just a lap belt. However, looking at the inside of the burb, there are tapped holes just below the headliner behind the second and third row seats. These appear to be original. They have the plastic plug caps that other front row shoulder belt holes sometimes have. I know that no suburbans of this era came with rear shoulder belts, but what are these holes for? I included a couple crappy pics of the locations of the plugs. Thanks to all that can help with this.
-Rob

[GuyO]

?? My Burb has them too!. And mine were white?? They do appear to be shoulder belt connections, especially because of the locations. Looks like GM just didn't pull the trigger on shoulder belts with the change of models coming in 73.

[sbrban]

You absolutey can run the boosters with lap belts. Use the lap belt and run the strap over the back seat and make a mount that bolts to the floor. Does that make any sense?
On the other hand, those holes are threaded and you can put in 3 point harness if you want to.

[tedfrk]

Just received the new brothers flyer in the mail and they have a kit for a pickup, but im sure you can get it to work in a suburban.

[engairuph]

ABI belts makes belts for aircraft that mount in the top and are long enough to mount to rear seat bolts are are retractable.