New boat, unknown transducer...

[TBarCYa]

I recently acquired a 1975 21' Regal cuddy and it has a thru-hull transducer installed but no depthfinder. I have a Raytheon Apelco depth finder from an older vessel that I would like to use and I'm wondering if it's possible to wire the installed transducer to this unit?? The transducer has a two pin connector plus the metal housing is connected to the ground of the cable. The Raytheon transducer is also a 3 wire but the plug housing is plastic so it's grounded thru one of the pins.

If anyone can provide any suggestions on how I may make this work, I would greatly appreciate it. I can't remove the thru-hull transducer and I'd hate to have to drill holes in the transome if there's some way to make this work.

Thanks!!