To clarify even further, not that anyone here would probably do this but you can still drive on the beach and even camp without the flag. It's needed when you go out into the dunes themselves
If you're removing it all for head gasket job the machine shop will/can clean all of that for you when they go through the head.
Or pull it all apart (rocker assembly) and soak it yourself to clean. Machine shop will do the head itself.
Yeah need more info, could have just not waited he full 20-30 minutes and thinks it's not going to turn off.
Grounding it works well. Doesn't bother me that it always turns on no matter what when the key is switched off