I see at least 4 "authoritative" sources for "bullet-proofing" system 80 games.
Each source highlights a handful of original board defects and an associated mod to eliminate the problem.
Everything from replacing individual resistors, to installing power confirmation LEDs on each individual pcb. seems to be "essential."
Im running on INFORMATION OVERLOAD at this point.
I have a WORKING BH and HH which I bought way back in 1995, but only recently brought out of "deep storage."
I never had to tinker with the boards, and I suspect a few of the essential mods were completed BEFORE I purchased the games.
Which "Bullet-Proofing" mods are actually essential?
-- Obviously the ground mods, but which others?
Which CONTEMPORARY (circa 2019) documentation source describes the MINIMAL mods necessary to ensure a long, happy game life?