This arrived yesterday: Bally Gold Ball - In a bit of a sorry and messed about state:

Quite a bit of the lower backglass artwork missing!





Hate those rusty coin door hinges

Playfield not too bad, Cabinet is very faded. All boards there, MPU got battery damage, looks quite bad.
Under the playfield is "interesting"



There is this extra part - It is a motor with some cams on it with switches on it. It has been wired into the existing wiring, so I started to investigate what the heck it was trying to do:
Firstly the motor is powered off the rectifier board - two wires soldered onto the bottom of the rectifier board !!! FFS
The wires that control the switches (4 of them) :
The first 2 uses the wires from the right slingshot switch (they have been disconnected from the slingshot!
The Second switch is wired into the outhole switch wires.
The wires to the right slingshot coil have been disconnected from the coil and instead run via additional wires to the outhole coil !!!!! The existing outhole coil wires have been disconnected.
So, it looks like this hack is possibly either to turn the game into a timed game, and/or maybe the solenoid driver board has failed so the outhole coil was not firing, so they have 'diverted' the right slingshol coil circuitry instead?
Here are these hacks:

wires off the slingshot coil and extended to go off to the outhole coil

Slingshot switch wires taken off the switch and diverted elsewhere.

Outhole coil has been disconnected and reconnected to the slingshot circuit effectively!
Other issues:

Diodes been cut on many of the other switches - so they wont work

Wire cut on the power board. Why?

The diverter gate has been made inoperable - there is a missing link between the gate assembly and the plunger assembly - not in the bottom of the cab unfortunately

The open and close gate coils have been disconnected.
There is an extra earth wire running from the earth connection on the power supply board up to a lamp circuit on the playfield??
The backbox wiring has been totally removed, including to all the score displays, looks to be all there, so first jobs are to reconnect up all the wirin, the set about removing the hacks and putting the wiring back to how it should be.
Then Test the PSU and make sure it is ok.
This is a two part project:
1. Get the game working as it should
2. Do all the cosmetic work needed

Quite a bit of the lower backglass artwork missing!





Hate those rusty coin door hinges

Playfield not too bad, Cabinet is very faded. All boards there, MPU got battery damage, looks quite bad.
Under the playfield is "interesting"



There is this extra part - It is a motor with some cams on it with switches on it. It has been wired into the existing wiring, so I started to investigate what the heck it was trying to do:
Firstly the motor is powered off the rectifier board - two wires soldered onto the bottom of the rectifier board !!! FFS
The wires that control the switches (4 of them) :
The first 2 uses the wires from the right slingshot switch (they have been disconnected from the slingshot!
The Second switch is wired into the outhole switch wires.
The wires to the right slingshot coil have been disconnected from the coil and instead run via additional wires to the outhole coil !!!!! The existing outhole coil wires have been disconnected.
So, it looks like this hack is possibly either to turn the game into a timed game, and/or maybe the solenoid driver board has failed so the outhole coil was not firing, so they have 'diverted' the right slingshol coil circuitry instead?
Here are these hacks:

wires off the slingshot coil and extended to go off to the outhole coil

Slingshot switch wires taken off the switch and diverted elsewhere.

Outhole coil has been disconnected and reconnected to the slingshot circuit effectively!
Other issues:

Diodes been cut on many of the other switches - so they wont work

Wire cut on the power board. Why?

The diverter gate has been made inoperable - there is a missing link between the gate assembly and the plunger assembly - not in the bottom of the cab unfortunately

The open and close gate coils have been disconnected.
There is an extra earth wire running from the earth connection on the power supply board up to a lamp circuit on the playfield??
The backbox wiring has been totally removed, including to all the score displays, looks to be all there, so first jobs are to reconnect up all the wirin, the set about removing the hacks and putting the wiring back to how it should be.
Then Test the PSU and make sure it is ok.
This is a two part project:
1. Get the game working as it should
2. Do all the cosmetic work needed