Fake alarm flashing light, sub 20$, about dodges three times

Would it not be easier to tap into the flashing light on the dash next to the clock?

 

That would be way too easy>>>>>>> I'm still on the fence about my plan to run 4/0 wire under the door sills back to the taillights to power my magical multi day fake alarm light mod

 

I'm going to look for that wire you suggested to use as the trigger for the adjustable relay, eliminating one of the fuse taps and the extra relay... good call, my friend... I wonder if that wire somehow involves the immobilizer system since it does activate when the truck is locked down... and I wonder if the wire, when I find it is "flashing" or if that is built into the little key symbol light....