The axle is held in by a retainer behind the brake drum. The are no c-clips on the Pontiac axle.

Take the drum off, and there should be an access hole in the axle flange to get to the 4 retainer bolts. Remove them, and the axle and bearing should pull out if it's not stuck, which it usually is. I use a slide hammer. Once the axle is out, you'll see the bearing and a collar are pressed on to the axle shaft. There is a seal inside the axle tube.

69s could have either roller or ball bearings, so make sure you get the right one.