The Squire had lap belts when I originally bought it, but the spear of death and my wife convinced me to install three point belts.
The B pillar has a good spot at the top to slip in an anchor plate.
The plates are 3/8" steel with a thick nut welded to the back. The seatbelt anchor bolts then screw into these holes/nuts. It's not going anywhere. I compared the anchor plates to some in the junkyard and these were clearly thicker and better mounted.
At the bottom, the anchor for the retractor mechanism.
The wagon has another spot that look suitable for backseat shoulder belt anchors. This is a shot of the inside of a parts car.
