I have a 1997 K1500, Truck has 180k miles on it and is a 4X4 5 Speed. Engine is the 305.

The problem I am having started yesterday as I was trying to leave for work. P Opened the door put the key in the ignition heard I rapid tick on the first key position then everything died. No dash board dummy lights nothing. Thought the battery was dead hooked up to a set of jumpers fed from the wife's suburban. Let it sit for 5-10 mins climbed back in and still nothing. No gauge movement, no dash board dummy lights.

This morning I was able to determine my clicking was coming from the interior light relay (BORG INDAK Made part) What else do I need to be checking for? Could this relay box be causing all those problems? Or do I have something much more expensive going on? Sadly its raining and the truck is outside but I need to get it running ASAP.