Found a tan visor from a 1500 that was in good shape finally instead of the mirror sagging. 
 

it has a light with a dimmer switch to adjust the brightness. I’ve looked in the 1500 wiring diagrams but I can seem to find where the wires should splice into for power. Wires are black and orange. I’m assuming black is ground and orange is power. 
 

does anyone else have a mirror like this is there truck or ever seen one of these?

Here is the wiring for our trucks.   This shows that it should be pink not orange, but orange was a typical hot leg color for interior lighting also.  If you don't have wiring up there, you can tap into any of the other light hots. (glove box is probably easiest to get to.  Notice it shows our drivers side should have a lighted visor even in the std model cab)

GL  HTH

Thank you! I will most likely tap into the glove box, makes sense to to keep it close. 
 

guess I shoulda looked into the 3500 manual and not where I was looking. Next time I know!