Hi, I've recently acquired two mac plusses which I'd like to restore to proper working condition. I've found a resistor on the back of one of the analog boards which looks very odd to me. Somebody has definitely been inside the machines before me, so I was wondering if this factory default for this revision or somebody has been hacking on it. As can be seen on the protective paper cover it has been running hot too. It seems to be rated 410k ohm, but measures 470k. Anybody familiar with this?