I actually just got done doing this to my truck. I went and bought an aftermarket kit for a late 90s dodge ram with low profile smoked cab lights. I promise you its worth the. Fight, but it can be stressful. The inner roof panel does not come out, you have to do it blind. I actually laid all my lights out first, marked where i wanted them all, then marked where the holes are for the screws to hold them down. Each light contains 3 holes (1 big for wiring, and 2 small for screws).
If you have ever played hide and go seek in the dark, its kind of like that, (you are permanently it and the wires always are hiding) easiest way is to take out your visors, then run long flexible wire from passenger to driver side, feed wiring in through the driver hole visor. Attach last light to your wire and as you pull it through start fishing each light for each hole, but careful not to pull wrong one through wrong hole. Its easiest to start at an end.