i believe my 77J still has its factory installed OECO voltage regulator.
the POH is very vague: it says Oeco and refers to a drawing number but there is no part number.
i wonder if anyone had experience replacing one of those with a more compact solid state type of device (zeftronics).
zeftronics has a few options but i am not sure about what i currently have and what kit would be needed to convert.
it is a pain to get to and i could not take a picture to clearly identify. ( i wish the regulator was installed on the firewall on the engine side.