http://forums.screamandfly.com/forum...ha+Excel+Lower
The 2.6 v-6 gearcases are all interchangable. The models prior to the 1986 model had a different shape than the 1986 and on. The 1986 and later were all the same housing. The 1.73 gear ratio was available only in the old stle gearcase for the v-6 Special also known as a 220. The Pro V 150 had a 2/1 ratio. The Pro V 200 and the Excell or 225 had a 1.81/1 ratio. The rest had a 1.86/1 ratio. The parts are interchangable in all of the later model gearcases. The 3.1 liter gear cases will all bolt up to the 2.6 even though a different size housing. They have some 1.75/1 gears in some models. Hope this helps. To the best of my knowledge they were all available in counter rotation.
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Hope this link helps!!
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