1) Pulled out the drawer and removed the shelf support bar.
2) used a rubber hammer to tap the broken guide and release it from the shelf support.
3) inserted the new guide into the hole openings and put a folded towel over the end of the guide to cushion the fragile end.
4) Then I lightly tapped the towel cushioning the end of the guide and it snapped into place.
5) Hopefully it will last for another few years. :)