I have a bathroom ceiling heater, fan and light unit (circa 1960's) with a wall switch with three black wires leading into one side, three white wires into the other side and one more line that looks like a ground. The online options available for the three switch units only have one line (hot) line and three load lines and a ground. Can someone point me to a DIY/how to resource. The inspector said this switch is arcing, and I do occasionally see a flash when I turn the heater switch off. This is my first post here - so I apologize in advance if this post is inappropriate in any way. Thank you

I'm looking to add 4' LED utility lights in the basement over the new work benches I just build by attaching them to the bottom of the joists but in one section there is a copper water line (for an exterior hose bib) that runs perpendicular to the joist which means my light either needs to go over (not desired as it would then be between joists and cast less light into the room) or below the water line and perpendicular to it. I will need to insert something like a piece of 2x4 below the joist to mount the fixture on so it clears the water line when installed. Is this OK to have a water line over (and run perpendicular) to the light fixture? Tony