thanks — i should have been more clear — it’s an EH 4250 B circuit board, which I believe has two stages (there are two trim pots, two op amps, lined up in roughly parallel circuits — and the trimpots are mounted on the top side.

the resistor soldered to the bottom, and the wiring of the bass switch seem to be less than the usual quality of the insides of a 70s EH product. or else this is an even hipper/stranger pedal than i thought!