Sont Watchman case opening???

[dtvmcdonald]

At the Eartly TV Convention I bout an old Sony Watchman,
a B&W CRT model with the strange flat picture tube, about a 2"
diagonal screen. Before buying I turned it on and got the behavior
expected tuning through digital stations.

Back home we have a Ch. 39 analog left and I have a Ch. 10
Blonder-Tongue modulator into an antenna. The video works
perfectly.

When I first tried it it the sound worked. Then it started
motorboating on and off and then when I tried new batteries
the sound didn't work at all. Probably a bad electrolytic.

I decided to open it up and see if it looked fixable. Its obvious
how to open it (unlike some of these, Sony actually had arrows pointing to
the correct screws!) and I got 5 of the six screws out and
was able to look inside, and it looks fixable. BUT ... I can't get
out the sixth tiny screw. It just spins ... and tying to pull
on the screw (easy since the back is fully loose) does not help.
HOW does one get these things undone?