Could be as easy as removing and refitting the "Galaga" connector - do this while the game is off.

If that game was "in front of me" - I'd refit the "Galaga" connector, reseat the EEPROMS, Refit the board ribbon cables and check the 5VDC at the "Galaga" connector.

Done all that - still no go....at least now I get a normal looking Galaga screen as opposed to just dots and lines.
Game appears to be really 'trying hard' to boot up - but it just goes to the normal Galaga Star background, has Player 1/2 and score info at top and level 'flags' at the bottom of the screen but NO fighter ship is displayed and no demo of the 'bees/ attacking ships' - it says Stage 1 for a second, then Stage 2, then Challenging Stage etc etc etc and just keeps on rockin its way up to Level 166 and beyond.

The guy is in Engadine in Sydney's southern suburbs - anyone know of someone who can service this for him - he will pay.

Cheers