Removing and replacing soldered parts without damaging the board

Steps

• Clip the failed part off the board, leaving as much lead as you can.
• Heat each remaining lead and pull it out with needle-nose pliers.
• Clear the holes with a desoldering tool, keeping heat to the minimum that does the job (too much lifts traces, too little tears out plated holes).
• When replacing a chip, fit a good machine-pin socket; avoid cheap stamped sockets.

Systems

• Williams System 11
• Williams System 11A
• Williams System 11B
• Williams System 11C

Source: Repairing Williams System 11 Pinball 1986 to 1990, Deel 1, Clay Harrell (pinrepair.com)