If its not too late, before you monkey around with the switch, Take the head off and make sure that the retaining collar that holds the module in place as well as provide the 2 mode function is tight. They can loosen up, especially if someone is playing with the hi/low mode by switching it back and forth a lot. There should be two indentations in the collar that needle nose or snap ring pliers fit into and snug it up. Do not try to torque it down super tight, but it should be a good snug fit.
Try that first before you pull the switch apart. I don't know if Gene is switching to the McGizmo switch on this unit yet because the Judco switch fits right in there. The McGizmo McCllicky is supposed to be going into the new MD3 and MD4 unit's tail caps as a drop in replacement.
Sometimes simply rotating the switch inside the tail cap assembly a half turn one way or the other makes switch contact issues go away. Usually loosening it up first and then just gently snugging it in, definitely not too tight on that. Keep us posted.