Mike have you tried any of STL's lights?
If you're doing the stobes for emergency purposes, definetly mount them in the brake/running light area of your tail light. If you want white lights, which would also be good, put them in the reverse lights. How about just some rear window mounted stobes?
Check out STL's products, they have some super sweet bumper and grille mounted LEDs. These guys make some sick lights.
edit: what about mounting some small LEDs in the bottoms of your ext cab windows for side visibility. You have the roof mounted light already dont you?