Re: arrow on piston
I have found the same thing from the same supplier. I concure about ring orientation. That's more important than a little arrow stamped into the piston.
This is one of those inconsistancies like carburetor jet sizes. I've found them to be nebulous. I never rely on the advertised/stamped or published size. Actually checking the orifice size is the only way to be sure of what you have.
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