Yeah I know. My 78 even had lamp cord wire going from the radio to the speakers and for the power cord to the amp. All put in my my uncle and his friends way back when
I would guess some pretty good sounding music might have ran through those wires. Nothing wrong with lamp cord imo for speaker wire IF the gauge is good. Sometimes that's pretty good copper and a fine twist, just sayin' I do own some monster cable for RCA cabling, none for speaker wire tho...always just go for heavy gauge.