May be a dumb question, but...

[PTmowerMech]

The Kohler V style valve cover gaskets, I noticed on the Stens website, there's 3 different model numbers, for what looks like the same gasket. Bolt holes look to be in the same places.
What's the difference? The thickness?

 

[Hammermechanicman]

I quit using gaskets on them. I put a 1/16" thick layer of "the right stuff" on a CLEAN cover. Install bolts till sealer just makes contact with head. Wait about a half hour then torque to spec. No more leaks.

 

[ILENGINE]

looks like 055-186 is an actual Kohler OEM valve cover with gasket, 475-006 is the stens aftermarket version of the gasket and 055-620 is the actual OEM Kohler gasket.