[67HEAVEN]

After removing the stock 1989 Silverado AM-FM-Cassette unit, I saw the stamped pinout information on the case about the various connections, like, speakers, etc.

What do the following refer to?

P-LT (beside the terminal marked GROUND)
DIM (next to P-LT on one side and Antenna on the other)
ANTENNA (next to DIM on one side and IGNition on the other)

P-LT? Panel light?
DIM? Something to do with dimming the dash lights including the radio?
ANTENNA? The radio has the typical large antenna connector away from the electrical connectors, so why the extra pinout marked antenna?

Thanks.