I used to have a 1516 for 20 years. It was never a favorite cab, my Mesa 215 was my primary cab, and I would add the 1516 to it for bigger shows.
Mine was the same era as yours from the late 80s: single 1/4" input and 3-way toggle for the horn (hi/off/low). Its a 4 ohm cab. It was never a 'master of anything' as the single EV15 didn't like alot of bottom end exertion, and despite the rating, those EVs can really only handle 200w and then fart out. I destroyed the 15 twice.
I would leave the cab alone, don't cut it up. Like already mentioned, people do search for them, so just sell it.