I’d look for the plastic screws that hold up the headliner, replace them with self-tapping screws to hold L-brackets up for the rear lightstick. Most lightsticks have the studs on a track so that you can align them where you want them. Make sure you get a TIR optic lightstick to punch through the tint & adjust the brackets so that the light stick hugs the window (or else you’ll have bad flashback)
For the front grill, I’d recommend mounting the light stick in the upper part of the grill b/c I think the lights are not effective if u mount it down low. However, when u do mount the light stick in the upper grill, use a light stick that doesn’t have clear lightheads (ie all blue, all red, etc) and choose a flash pattern that provides a large footprint/block of light (if u have small split patterns or multiple colors then they’ll get drowned out by high beams at night)