The factory used a veneer on all of these examples to hide the F tuner screw pilot holes. I didn't even acknowledge them until I bought a fire damaged Coronado with the veneer peeling off the back.Then each time I saw a guitar with these I inspected for a veneer.Sure enough all the factory original examples had the veneer.

This first style grounded to the bridge by a guitar string that was placed in the thimble hole and bent to make contact with the pickguard.

Second generation styles had a V notch cut into the master control tub with a black (sometimes green in mid 60's) wire running to the tailpiece route.

Darker custom colors like black, charcoal frost, Ocean Turquoise, etc use a CBS logo with "Fender Jazzmaster Offset Contour Body Pat Pending" in gold and the rest in black. For referance, here are some comparisons of Seymour Duncan Jazzmaster reissue pickup next to a genuine Fender 1959.

The shielding changed a few times in the first 6 years of the guitars production.

The wire was grounded via a staple on the face of the guitar below the tailpiece mounting plate.

The tub design first changed with the rhythm controls section in 1962.

They also unofficially sold these gears on some guitars.

Mainly they are found on Coronado's, but I have seen them on four Jazzmasters, one Jaguar, and two Stratocasters.

If it looks like a Coronado headstock or like an older smaller Jazzmaster headstock, then the neck is not a Jazzmaster neck. Earliest F tuner equipped guitars feature Kluson tuner hole piloted necks with factory filled screw pilot holes.