@autospec, Maybe this will give some insight on your mirror imaged cornwall speakers. Mirror imaged cornwalls were discontinued in the year 1974. I think!, the style # the C- means cornwall the M- means Jensen woofer,K-33-(M). And the 7-15 means they were made in the 15’th week of 1974. All cornwall’s, made with vertically aligned transducer’s were not marked left or right. I hope that help’s. :-) Mike