actually geoff... yes....

When i bought it, it came with a wiring diagram.

It is a lot simpler than it looks to be fair when you stick your head inside it !!!

For an old machine, apart from a bit of denting to the pannels, the only things ever gone wrong are:

1) A microswitch moving out of align stopping the weapons firing.
2) A wheel bearing mounting needed rewelding.

Very well built machine !!