blue wire passenger side under carpet runs near backseat?
not trunk light, rear defrost on convertable?

 

Rear speaker probably.

 

oh yeah! Duh
On a convertible where do they put the rear speakers there’s no package tray

 

In the vertical seat back; the divider between the passenger compartment and the trunk. I can't think of the official name for it.

 

I might add that a rear speaker (option code U80) in a convertible is behind the rear seat on the passenger side and is essentially useless when the top is down - can't hear it at all, or at least I can't!My '68 has a factory AM-FM non-stereo radio with a rear speaker so, when the top is down, I just put all the output on the front speaker and still get full sound. My '69 has the factory AM-FM stereo radio and, when the top is down, you just lose half of the sound as there's no putting all of the sound to the front speaker. By today's standards, the sound that comes out of those old factory radios just isn't that great. But, that was the hot item of the day - if you had a radio - any radio (AM, AM-FM mono, or if you were real rich, AM-FM stereo) - with a rear speaker, that was special!

Randy C.