As long as the multi-piece arm contacts the cam across the full width of the face, no problem. I'd use a little Prussian Blue indicator dye to check the cam contact footprint, and correct it with a fine grit belt sander if necessary. Are you smarter that the 12 year old slave laborer who put the pump together in some third world sweatshop?
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!