My oil pressure gauge is pegged. Any ideas?
Where is the sender for the gauge?

Also, my temp gauge goes nuts sometimes and pegs. Where is the
sender for the gauge?

Anybody know where I can find a free wiring diagram?

 

oil pressure sender should be on the drivers side of the block down by the 02 sensor.. my 87 oil pressure was pegged, and i changed mine, and it went back to normal.. as for temp sensor you should have 2 one for the computer... and one for the gauge... 1 is located on the drivers side of the engine, by the manifold, towards the front of the truck.. and the other is located on the intake manifold up front, near the thermostat housing...

sometimes when the gauges are going crazy, its normally due to poor grounds also. just something to keep in mind.
as for the free wiring diagrams, im not sure about that.. but if you plan on keeping the truck a good service manual.. NOT CHILTONS/HAYES.. will tell you everything you need to know about your truck. the only downfall is there quite pricey, at about 100 bucks or so. sometimes you can get them cheaper on ebay/craigslist
hope this helps

Ck1500

 

I had a plugged PVC port on my TBI that was the cause of my high oil pressure. Once i rebuilt my TBI and cleaned all the carbon deposits my oil pressue went back to normal. Just another possibility.