Where is the oil sending unit located on 1995 Chevrolet truck 350?
On the drivers side next to the distributor.
The far right side of the instrument cluster. Or, did you mean the fuel level sending unit? That's located inside the fuel tank and is part of the fuel pump module. To replace the sending unit you have to replace the entire fuel pump module, which means removing either the fuel tank or the truck box.
I have a 1995 Chevrolet K1500 Extended cab Silverado and I can tell you that I've been having heck with that problem. Yes, it does have a relay and it is located in the fuse box under the hood on the driver side. If you're looking at it from the front of the truck it will be the black relay box on the left hand side of the fuse box. Should be just fuse and…