Has anyone replaced the o ring on the dist shaft before? It's the only one on the shaft toward the end. After my used distrib was installed, it's been leaking at the bottom of my dist cap down on the motor constantly. The shop is gone and I wanted to know if anyone's done it before. I did it before on my old Mazda but want to make sure I don't scratch or gouge the shaft. I know it's probably very hardened and it's so narrow I don't want to gouge the shaft if I try to cut the old o ring and defeat the purpose of trying to fix it. The o ring is 'beveled' and is $3 at Nissan. They want $75 just for labor!