Polysix battery

[jhaible]

Hi,

I know it was a topic many times before, so I'll keep the question
short. I just bought a Polysix with the typical battery leakage. It
was cheap, and I intended to use it for parts, but the leakage area
is rather small and the synth looks good apart from that, so I consider
to restore it. I know about checking the corroded traces and so on.
I just need three things:
(1) Which battery to use ?
(2) Will it run without battery, so I can test the rest of the synth before
      I buy a new battery ?
(3) Can I simply unsolder the two prongs that hold the battery, or is
      it of the kind that will explode when it gets heated ?

Thanks in advance, and thanks for all the tube safety information, too.
(I guess I would have run into the trap with the grounded scope ...)

JH.