New O/O, Old truck what do I need to keep her in top shape?

I was thinking maybe they couldn’t find the replacement part. The wire I took off was 8’ long and had to call a few different shops to find one. Even then it was discontinued and no one had it in stock.

 

I went behind the dash because I noticed the pyrometer needle wasn’t moving at all and to look for old wires etc. When I went under the hood, the pyrometer was wrapped up unplugged near the exhaust.

 

Yeah I need a new thermocouples and an extension wire that plugs into the back of the pyrometer gauge. That’s just to start out. I’ll be looking deeper at the truck here soon

 

I’m not in a mountainous region but it is fairly hilly butt regardless I feel if it came like that from the factory with one for a reason. I also do not think newer trucks have one.

 

Anyone know if these trucks have schematics, or build sheets? I tried calling a local M&K truck center and they said they used to make old parts catalogs years ago. They also said they have schematics for each truck listing every part they have but its dealer use only.
I’m looking for something like that to become more familiar with my truck, the parts and part names.

 

When’s the last time y’all seen one of these? Before I bought this truck I had never come across one Hahaha. From what I’ve been told it’s an old “cruise control”. Can also be used for heating up truck, and speeding up the process of raising the end dump trailer.