The game rules for Gottlieb Pins Series System 80 and 80A are stored in 2 Eproms (U2 and U3), these proms are 2332 Eproms. These proms are hardly available and to my knowledge there are no current Eprom Burner which are able to burn these proms.
After 20 years it is likely that these proms are going to fail.
At Marvins side it is described how to substitute these proms with a standard 2764 Eprom. However for this there are some wires to put on the board. With this adapter wires are no longer needed.
layout, click to enlarge
The adapter (front and back)
and fitted :-)