We just built an undercover one and it was one of my favorites just because of how undercover it was. Here is what you can do:
Feniex cannons 120, In the rear backup lights, replace the backup bulb, and in the lower reflector area on the bumper (you have to "burn the hole in, as a drill bit will go to deep).
You can also mount them next to the license plate lights facing down. This will give you additional warning flashing off the liscense plate light when the tailgate is down, but when the tailgate is up the license plate lights go up with the tailgate and face backward when the gate is up.
For the grill, Federal Signal Micro pulse 300 worked Really well in the grill slats. we used 4 of them. You will have to fabricate a bracket but there are bolts to attach it to.
Do you have fog lights? If not, get the fog light housing and mount a cannon inside of them.
And for my next trick, Flash the DRL led lights. (as a note, the headlight are NOT the area that is more in line with the "jeep" badge. This is the the DRL and Turn signal, They are lower, kinda hidden, and they are projector). Money poorly spent trying to put hideaways in there, BUT you can flash the drls with a standard LED flasher, it is just a little tricky. Jeep sends a 12 volt signal to turn them on (which is what you would tie into) and then they send a 12 volt signal to Dim them (which you would need to isolate) The dim function is on when the headlights are active, so even if you put in the flasher, as soon as you turn on the headlights, the DRLs will be in "DIM" mode, and so will the flashing function. If you isolate that, they will always be bright.
To mount the stuff, there is a hidden compartment under the passenger seat. We cut out the bottom and mounted the fuse block and HHS2200 siren to the floor. To access each item you move the seat forward and back. That was pretty much the only area to mount stuff in this beast.
The gun lock is neat how it worked out. The area that it is in fits an ar-15 perfectly. And we control it by a hidden magnetic switch mounted under a plastic panel somewhere in the vehicle. You have to know where it is at to pop the lock.
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