hey everyone...i know i'm getting old...and it's been years since i've been inside a motor. But i'm putting the top end back together on my 1992 900 SS and i know there are 5 O rings, two horiz and three vertical. And as i layed them all out ready for the install, i've found I have a sixth that is the next size larger than the two smaller ones. I've looked through the blue shop manual but cannot find its home. ???