another am radio question HELP!

[freezmcnally]

ok. been searching but i dont seem to have the wiring spades listed as others do...or im confused...or both.

If i hook up power to the 12v spade and ground the radio...it remains dead when grounded. knob on/off makes no change
if i hook up power to the unmarked middle spade, it lights up when grounded.
knob on/off makes no change

everyone says hook power up to the one that says 12v. but it only looks to work when i do it on the middle one...so im confused. haven't even got to the sound part yet