I bought this pick up and noticed the temp gauge is always cold and doesn't move and the oil gauge is always pegged on high even with truck off. I replaced the temp sensor with no change and can't find where the oil sender is.

 

Try looking for the guage fuse first to see if it's bad.

Sometimes the guages just go bad, too.

 

the oil sensor is on the driver side of the motor it is located more towards the firewall i replaced this also it only cost about 10.00 at autozone