Water Temperature Sending Unit - Part Number Confusion

Water Temperature Sending Unit - Part Number Confusion (1978 220hp 305 cu. in.)

I have a 43' 1978 CarlCraft houseboat with twin Crusader 220 V-drive engines (220hp, 305 cu. in. displacement). One of the temperature sending units is bad, but I'm not 100% certain what the replacement part is. I have it narrowed down to part numbers #22701 and #700427 (superceeded by part #R020003).

Can anyone clarify which part is correct for my engine? I'm leaning towards part #700427 / R020003, but I found another post in the Crusader forum which recommended part #22701. However, that was for a 1990 454 cu. in. engine.

Thanks in advance for your help!
Wes

I'd go the way you are leaning, if you need the single station version.

A limited 'reverse' search of some crusader parts listings shows the 22701 as a dual station version. Looking at its infered mounting location, it's possible its thread size differs, too.

using your searial number would be the foolproof way to determine the correct unit.