88 Gmc C2500 Shutting Off Randomly

[88 GMC Truck]

I hope that you might be able to identify a problem No One to date can seem to troubleshoot. I have a 1988 GMC Sierra 3/4 extend/cab that I have owned since new. About 5 years ago it was stolen from my home and recovered a few hours later. Needless to say the thief broke into the steering column to start the truck. In doing so ,some wiring was damaged and need repair at the dealer. All seemed ok until the truck, a couple of years later, started to shut off like someone reaching over and turning off the key. It was diagnosed as a failing fuel pump. The truck had a little over 200K on the ticker at that time. So in went a new fuel pump from NAPA with a new wiring harness that goes inside the tank and which is connected to the new pump. Well since that time another three pumps have been installed in as many years because of the same symptoms and now in less than a year it appears that its fuel pump time again. To be honest with you I don't think its the pumps anymore. Somewhere I believe there is a short but where is the question. All the outside sensors switches fuses have been replaced along with a new engine transmission etc. and its doing it again. I noticed in a previous post to another GMC owner you mentioned that you have an electrical chart for his truck. Do you have such a chart for the steering column for my truck by chance? And is there anyway possible that a cruise control switch/ arm could cause this to happen if it had a short in it? The reason I suspect the original cruise switch is that a few years ago, I lost the ability to engage the cruise control. But recently after installing a new ignition switch it started to work. I thought great I found the problem NOT !!! . As soon as I wiggled it it would quit working again. The truck stayed running but the cruise quit. Then it wouldn't reset again like before. Now sometimes it does and sometimes it doesn't. I can disengage it just by turning the turn signal/cruise control arm ever so slightly. I'm not sure if there is anything related but the truck is still shutting off randomly. I was wondering if electrically there is ANYTHING in the steering assembly that could short out turning the engine off! Any thought or suggestions would be greatly appreciated!