<VV> Crankshaft (not camshaft) Gear Question

[Steve & Doris Schwartz]

I have learned I was looking at the crank gear when I cited those Clark P/N's in an earlier post.  I also learned that there IS a crankshaft gear for the 140 automatic and another for the 140 manual transmission engines.  There is a 4 degree difference between them.  I bought a used one when the engine was rebuilt 5 years ago (new ones were "out of stock" at the time)...and was not aware of the difference.  Perhaps it's not even the right one for a 1965 140 for all I know...1960-63 are different from 1964-69 (?).

So my question is, what can I expect from installing a gear intended for an 140 automatic on a 140 engine with a 4-speed transmission?  Power- and performance-wise?  How about one intended for a '60-'63 (possible?)?

Is there a way of telling via visual inspection that I have the wrong gear for this engine/tranny combination?

If I need to change to the correct crankshaft gear the engine will have to face a complete teardown...is that correct?

Thanks,

Steve
140 VAIR