My daughter aquired a 1987 Skyhawk and needs to replace the lap belts in the back seat with lap and should strap belts in order to use for her children's carseats.

I need to find the GM retrofit seatbelts or at least find out where the anchor points are on this model. I found out on carseat.org that this vehicle does indeed have the reinforced anchor points and that GM did make retrofit belts.
Unfortunately, I called GM and they seem to be clueless.... Any help would be very much appreciated!