I have just gone down this road with our 16 ft Bonito hydro lift mklll. 20" motors are harder to find 2nd hand and new was out of my price range. Replaced a 1991 Yamaha 115hp 2 stroke 20" with low hrs Johnson 25" 115hp 2 stroke 2004. The transom was built up 5" with an aluminium plate $520.00. Very happy with this setup the boat handles better with this engine, less water comes over the new transom and with the engine higher it no longer gets dunked in the water at rest in a rough sea. The new engine is a little smaller and lighter except for the leg.
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