In the process of renovating my basement, I want to install light dimmers at a few locations. At one location in particular, I am having a hard time figuring out the wiring diagram and would appreciate some help.

Please see attached pictures and a sketch of existing wiring diagram.

The junction box on the wall has an existing light switch and an existing defective light dimmer side by side. Both of these serve one light fixture. I am trying to install a lutron light dimmer (switch and dimmer in one).

Other than the one light fixture, I *think* the wiring for two wall scones also come to this box. I am not sure because I have never installed a fixture for the scones to test it out (it is just an open junction box now with wires capped). But there is no other place for a light switch for these sconces. I would like to make sure the scones are also wired properly so that I may install fixtures for them in the future.

There are three romex cables that come into this junction box.

Anyone know what is the proper way to wire this for the new dimmer switch? Also, does it look like the wiring for the sconses come into this box? Do I need two dimmers, or one dimmer and one switch, or just one dimmer?