Position the track so that you are looking at the bottom (View A). Slide inner track toward the front, so that you can access the dimple on the outer case. Remove the dimple that is located just inside of the hole by striking with a blunt punch and hammer.
Turn over the seat track (View B), and slide the inner track toward the rear. Be careful to catch both roller wheels and the old guides as they fall out.
Slide the inner track all the way to the front and put the roller in place and install the guides into the slots, one on each side.
Now slide the track back towards the rear, and install the guides and roller at this end.
Re-punch the dimple so that the roller cannot advance past it.