Alpha 1 Trim Cylinders (two sizes)??

Who knew that Merc made two sizes of trim cylinders 15 9/16 and 16 3/16 for a A-1. I have been running a Alpha SS for some time and noticed drive could use more negative trim out of the hole.. Measured cylinder, was the longer one, 16 3/16. Question, what trim cylinder size did Merc use from the factory for the SS?

When I installed the shorter drive for the old A1, never entered my mind there were two sizes of cylinders. Searched the net but to no avail. Anybody?

I wasn't aware of that either, but did you know SEI offers both
lengths for $120.00 each?

http://www.sterndrive.cc/Mercruiser-...Cylinders.html

Thanks for the search GC. Darn good price and will think about purchase. Do you think the SS is shorter width wise vs a Alpha1?

Also want to add 1988 18C.

I believe I read it's the same.