I too have a 4m Narwhal, mine came with the 2-man jockey console fitted. I presume yours has the ickle front locker wiv top-opening hatch? The front of my console is about 10-12 inches from the end of the front locker. This gives loadsa room for engine tilting at rear, and the balance of the boat is fine. I have a 40hp 2-stroke sitting on the back, with fuel tank under the jockey, and battery immediately aft of the jockey, so would imagine that sort of position would suit most 30-50hp motors (give or take an inch or so).
Hope this is useful....
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