Explain?
drill through the cell closest to the switch and collapse the cell onto itself.
If this was directed at me, I'll try..
But it's been about 10 years...
A 3D Mag. Sitting for a few years. Stuck Ray O Vacs.
The cell closest to the tail cap and the middle cell came out easily enough. A little WD-40 and some persuasion..
The cell closest to the switch was the completely corroded cell. So I took the switch out from the front by removing the spring clip.
I then used the longest and largest drill bit I could find. I'm drawing a blank on the size. But I drilled through the center of the cell. Then I used a hammer and large flat head screwdriver to collapse the center onto itself. That took a bit of time.
Then I used a cylinder hone to clean up the inside of the tube.
Hope this helps..
As an aside, if the light hadn't had sentimental value (it was Dad's last department light before they switched to MagChargers) I would have just sent it to Maglite for replacement.