Installing tiny little o-rings

Working through a problem with Brocock Commander fill port leak (apparently a common, known issue), I was graciously sent the proper tool and replacement o-rings by AOA (Kudos on their CS skills). It was apparent that getting this o-ring onto the miniature piston was not going to be a breeze, but I found that a 7/64" drill run through the tip of a salvage cheap ball-point pen was perfect. Just lube the o-ring up, slide it onto the pen tip, then plug the piston into the pen tip, slide the o-ring down the tapered pen tip right onto the piston. Bob's your uncle. Hang onto this high-priced tool, you'll need it again.

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