Im trying to install a new light fixture in the front hall. Current light is activated by 2 switches (on each end of hall). The NEW fixture has 1 black wire and 1 white wire. The ceiling wires have 2 black and 2 white coming down. The OLD single light has the 2 wires connected separately by a lit...

Since the red wire is already being used for the outlets, you'll need to run a pair of 3 wire cables from the existing switch box to the location in the garage where you want these light switches. This is what you'll likely have to do: Here are some other options: Image Source

I'm trying to install a new light fixture in the front hall. Currently, the light is activated by 2 switches (on each end of hall). The NEW fixture has 1 black wire and 1 white wire. The ceiling wires have 2 black and 2 white coming down. The OLD single light has the 2 wires connected separately ...

Should the dope be applied directly to the male threads or should the tape go on first?

For threaded plumbing connections, you typically use pipe dope or thread tape (aka teflon tape). Are there situations when one is preferred over another? Does the size of the pipe, type of pipe, parting being connected, or other variable make a difference in the selection? Note, this assumes you...