I plan to use the tailgate release circuit to trigger a relay and have the bed lights come on and stay on for a period of time. Hoping to grab 12v for the relay from the lighting circuit in the rear. Using one of these adjustable timer relays. (ive used them before and they are great) https://www.amazon.com/dp/B07JC38GLS/ref=cm_sw_em_r_mt_dp_2SM8Y740QSXPHX2VNJVJ
If you have a bed cover and dont mind your bed lights on all the time...you could use a diode and pig tail at the bcm plug to jump headlights to bed lights. So bed lights are always on when the headlights are on.
