Definitely and add-on, not sure if you have an Aspy or Interstate but the Aspencade had the i/c (could be a PTT ike Joe said) and looks like there were the little pouches on your trunk. Are there mounting holes on the front top corners of the trunk too? If so someone added the SE rear speakers somewhere along the way; did that to my '84 Interstate.
Just a though, the Aspy pockets were different than the SE ones, the SE ones integrated perfectly with the appropriate pouches, but not with the Aspy ones. Left a bit of a gap in places, don't ask me how I know