I've finally got my watch back together, working/beeping properly. I would like to thank you all for your help in getting my watch together again. Special thanks to Van Malan for the 3/4 inch socket tip. I used a 1 1/16 socket and the caseback, literally, glided into place. I now can change a battery with my eyes closed...really.

So, Here are my Step-by Step Instructions for changing the D/L 150S watch battery.

1. Pry off the caseback with a pocket knife. Use the blade, not the tip of the knife (The pry tab is at the 7:00 position).

2. Peel the red tape off the battery.

3. Push the Spring-Clip (at the 6:00 position) down. This should make the retaining tab (in the hole at the 6:00 position) pop out. Release the pressure from the clip and it should pop up. If not, you my need to pry the tab on the spring-clip with a small flat screwdriver.

4. Slide the old battery out.

5. Slide the new battery in. (+ side up)

6. Push the spring-clip down until the clip snaps into place (6:00 position).

7. Put cellotape over the battery and the spring-clip.

8. Ensure that the little speaker spring is still in place at the 7:00 position.

9. Make sure the o-ring is still in the groove on the caseback.

10. Lay the watch on a solid piece of wood with a piece of foam between the wood and the watch face.

11. Place the caseback on so the pry tab is at 7:00 and the speaker disc is over the battery.

12. Place a 1 1/16 socket on top of the caseback with the open part of the socket facing the caseback.

13. Take the whole mess. (wood, foam, watch, caseback, and socket) and clamp them together with a "C" clamp.

14. The caseback will pop into place.