There is an end play spacer that sits in the "stack" that determines endplay. The endplay spec is .0016-.0028". The spacers can be selected in various sizes to produce the amount of endplay neccesary. The torque of the from pulley does have a slight effect on ultimate endplay. The inner boss of the aftermarket one-piece pulley or the hub of the stock pulley rests against the stack. More torque applied to the tension bolt holding the pulley to the e-shaft will produce a very slight loss of endplay. So the answer is that the pulley does not directly set endplay but the torque of the tension bolt does have a slight effect. Re-torque that bolt to factory spec and you'll be fine.