i just recieved my alta tensioner stop in the mail. It shows having the tensioner removed for installation. is this necessary? I already installed my pulley and returned the rented pulley removal tool (haven't been credited back for pulley tool though- need to call alta)

 

You don't have to remove any pulley to install this, so I don't see the worry about the puller. People have installed the stop w/o removing the whole assembly though.