And after a lot of work, one of the infamous Duke cabs has been restored.
I'll get some much better photos when I can actually put it in the middle of a room instead of blocking the lounge doorway

There was no space in the house but the rain kept stopping me working on this, so I put it inside anyway.

Work list:
Cabinet stripped
Cabinet cleaned (gently!), metal rails removed, polished and refitted with new tacks, t-molding polished, some slight edge damage on the black touched up here and there.
Coin door totally stripped, cleaned, polished, all parts replaced or de-rusted and polished (note: bulbs are still in the mail somewhere...)
Control panel stripped, trackball stripped, cleaned, de-rusted, rebuilt - may have new rollers made so I have spares, unique Sidam part. Bearings reconditioned due to difficulty getting new ones that were free running enough. Buttons dismantled and cleaned. Panel cleaned and polished.
All metal control panel mounting parts cleaned and re-plated where required.
Black metal trim all removed, cleaned, polished.
PCB caps replaced.
Power supply stripped, new line filter, rebuild with new diodes and caps, new power cable made up.
Monitor stripped, shielding de-rusted (created a WHOLE PILE of rust+paint from this part alone), rust protected and primered, chassis dusted out, rebuilt - did not explode, very happy.
Bezel reinforced to restore to correct shape as far as possible - may work on this again sometime to make perfect.
Light fixture and marquee cleaned, new strip light, found someone had disconnected the speakers. No idea why.
Then it was all put back together again, new screws/etc where possible, earth terminals polished and tested.
Turn on, go deaf due to volume being up so high. Lose in round 1, always the same for me.