The principle is simple, but the fabrication can be challenging. When we changed out the OEM Universal diesel for a new Betamarine, the throttle did need to be reversed. Interestingly enough the old Universal did have a little actuation reverser mounted on the engine, as supplied by Universal. Our engine installer fabricated one for the new Betamarine. I have a picture of it in a blog entry. The mechanism is simple, but then you have to find a place to attach it.
Picture #2 in this entry shows it well, and I could take some more if requested.
These photos show the Halon bottle in place, and also a much better look at the inside of the compartment where the meter and terminal strip are mounted. As an "extra" there is a shot of the new coolant overflow tank showing how the level in it...
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