A non digital friend just bought a 95 Searay, 31' and it has the stock
Lowrance depth finder with a round digital readout. He would like to
replace this unit with a very good Lowrance or other depth and
fishfinder and use the same thru hull hole. How does one go about
finding which transducer is compatible with the existing hole. The
fall back position is to make the hole larger but he definately does
not want to drill another hole in the hull. Also it would be nice if
he could keep the existing digital readout on the console and add the
fishfinder screen.

Thanks