Javier,
Are you concerned with correctness, or just a good system that doesn't look out of place?
The stereo had a separate multiplex unit mounted in the trunk. I don't know if it would have been elsewhere in the vert, since it would have been at about the same place as the pump. Also, no idea where the correct rear speakers, if any, might have been. I think correct will be hard. Unapparent should be pretty simple, though I'd suggest avoiding the correct door speaker boxes. I think you have better choices for placement that are out of harm's way.
Good luck!
Michael
------------------------------------------------
OBSESSED with the arrival of my 68 Shriner?s
vert!