I just wanted to give an update on the restoration progress..
The game pcb appears to have been soaked in WD40 in the past (a really bad thing for electronics in general), but most shockingly (literally) i believe that when the high voltage went out on the monitor, it may have arced across to the game pcb. This would explain why every single 4116 ram (16 of them) and every single 2708 eprom (12 of them) plus both CPU's, PIA and AY3-8910 sound chips were all stone dead, with many of the eproms and rams burning hot and shorting all sorts of pins horribly.
After replacing everything that needed it, the game can be seen to play the attract mode, but it still has some major colour and graphics problems. here's a screenshot update :

There's still more work to go, but its good to have something happening onscreen finally.