A-numbers versus the 5xxx number on the board

The A- assembly number for a WPC board comes from the manuals and is usually only on a sticker on the component side. The bare board number starting with 5 is printed on the solder side. Use both when identifying or swapping boards.

Systems

• WPC Alpha-Numeric
• WPC Dot Matrix
• WPC Fliptronics
• WPC DCS
• WPC-Security (WPC-S)
• WPC-95

Source: Repairing Williams/Bally WPC Pinball Games from 1990 to 1999, Part One, Clay Harrell (pinrepair.com)