First, the long stem protruding from the back of the radio is there to help locate the radio inside the dash. It has nothing to do with whether the radio works or not.
Now, as far as the three colored, multipin connectors are concerned, I think I already told you that all three are not used on the '93 and '94 systems. The pink was is used on top and the middle one as well, whichever color is plugged into the bottom is a dummy. You will know instantly whether it's the brown one or the grey one based on whatever you have in your truck now. If you have a grey connector that's wired than the brown one is the dummy. Like I said, I can't remember which of the two, grey or brown was the dummy.
So, it you have the pink and grey multipin connectors plugged into the back of the radio, the CD DIN plug connected and the two antenna wires marked sub and main plugged in the radio should work once the code is entered. If you don't have the sub and main antennas plugged in you definitely won't have the radio working properly.
Now, as far as the three colored, multipin connectors are concerned, I think I already told you that all three are not used on the '93 and '94 systems. The pink was is used on top and the middle one as well, whichever color is plugged into the bottom is a dummy. You will know instantly whether it's the brown one or the grey one based on whatever you have in your truck now. If you have a grey connector that's wired than the brown one is the dummy. Like I said, I can't remember which of the two, grey or brown was the dummy.
So, it you have the pink and grey multipin connectors plugged into the back of the radio, the CD DIN plug connected and the two antenna wires marked sub and main plugged in the radio should work once the code is entered. If you don't have the sub and main antennas plugged in you definitely won't have the radio working properly.