Remove the drawer, remove the shelf bracket from the back of the refrigerator, it simply lifts out at an upward angle like any normal shelf bracket; remove the broken pan slide by sliding it “forwards” out of the tabs locking it into place; if it is tight, gently encourage it to move with a slight tap (light hammer etc). Align the new pan slide into the holes (be sure to properly orient the slide). And then slide it back to lock it into place. Replace the shelf bracket and the drawer....
Easy