How about no mods (a shocking confession).

27 years up and running ok without doing the typical board mods, on six System 80 games, in a mostly dry cellar. Cleaned up any PCB corrosion. Card edges got cleaned or retinned, a few pins and connectors were replaced, and some contact cleaner was applied. That's it, and some of these games came from damp storage. The games have been solid, except for cracked headers developing on the PSU's, and remote nicads, in plastic bags, wicking corrosive juices back up to the boards.

Did the John Robertson flippers.com version of the grounding mods this year, mostly for peace of mind. Figure those mods are a must for anyone that would operate or leave the games unattended. I've had thousands of boards through here, including quite a few burnt Gottlieb driver boards.

Opinions will differ. Let's agree to disagree, and keep it cordial.