Which one? There are several.
It is located on the brake pedal arm under the dash.
under the hood in the main fuse box by the pcm (drivers side has fuse box written on it) look under the lid of the box and it will tell exactly which relay it is
How do you change the ignition control module in a 1988 Chevy Silverado 5.7L
How do i change the ignition switch in a 1988 Chevy camaro
There are several relays on that vehicle, need to know which one you are looking for.
The gross weight of a 1988 Chevy Silverado K2500 with a 5.01 engine is about 2.5 tons. This is equal to about 5,000 pounds.
Chevy trucks did not have a inertia switch. You need to check the fuel pump fuse and relay and then make sure you have power back to the fuel pump that's in the fuel tank.
That would depend entirely on which relay you are referring to.
how do install key ignition switch 1988 Chevy s10