Bought the replacement part at AppliancePartsPros.com using cross referenced item. It was exactly the same as the part listed for GE PS4S6PGZBESS refrigerator. Part arrived in a couple of days. Only real installation was snapping the clear plastic front piece from old part into new part and sliding shelf in by lowering it into place and pulling down a bit to make sure it was fully inserted.
I cautiously snapped the front clear plastic piece into place prior to installing shelf in fridge. Feared I might break something but it snapped into place easily.