Hello,
I purchased an acid damaged polysix from ebay back in march, Its repair was left in the hands of a very reputable synthnerd, in Dublin.
I would say its 99% there, with one problem, 2 of the voices have varying tunings across the keyboard.
The repair man in question has changed many parts across the various boards, aswell as re-cleaning the boards themselves.
In fact he's even got a detailed blog on the P6's repair at:
http://www.retroactivesynth.com/index.php/blog/march-2011Scroll down slightly.
The next part he is planning to replace is the multiplex, hes not very happy about this as he has tuned, and retuned extensively.
If you have had to deal with something like this before, and have any suggestions we would love to hear them,
Thanks,
Carden