pull the plate off the dash where the cb is strapped to
Assuming you're referring to the North American VNL series, it should be in the centre of the dash.
Is it not on the inside of the fuse-box cover?
Under the dash above the radio remove the plastic panel this is a common place for the CB check under there.
behind the ashtray
The 1966 Chevrolet truck fuse box diagram can be obtained from most Chevrolet dealerships. The fuse box diagram can also be found on the inside cover of the fuse box.
The fuse box can be found in the engine compartment. The fuse box is located on the drivers side of the engine compartment.
Remove the ashtray. Then lift up and out on the tab labeled "Fuse Box"
this, like the trinity is a mystery
The fuse box is under the hood on the driver side (left side), of the engine beside the battery the fuse box should be in the same spot if the truck is a gas or diesel.
Where the fuse for the side rail on my truck
Well..... Our Chevy Trucks fuse box is under the hood up front with the engine. Drivers side of truck under a very secure plastic box. It says Fuse-Relay Center on the box.