I didnt mount it outside the bumper.... Lol, Cut the lower grill and set my inside the bumper. Thats what I did. THere is no way at all that someone cant just take the bolts out. There are tools to remove any type of bolt out there. Just make it as hard as you can.
You can always weld covers over the bolts but then you couldnt remove it either haha
If someone wants your shit they're going to find a way to steal it. The world is full of degenerates. Get modified vehicle insurance if you're concerned.
If you already have an aftermarket alarm, this isnt hard to do.
You put a hood pin underneath it. that way if it tries to get unbolted the alarm will go off, but then your light bar will probably be gone at the point anyway.
Who knows maybe the person will freak and drop it and run.
Best way is use unusual bolts to secure it down. Random torque sets, different size/pattern bolts all help to slow them down and possibly deter thieves...
but all in all thats the shitty part about any simple bolted exterior mod. Its an easy thing to get stolen.