The belt tensioner pulley on your 1995 Buick Park Avenue is generally replaced with the tensioner assembly. The belt tensioner on your Buick is quite complicated as engine coolant passes through it. The complete tensioner is a bit difficult to replace but not that bad. If you would like to replace just the pulley you can but you may need to purchase the complete tensioner to get a new pulley. The bolt that holds the tensioner pulley on is "left-hand" tread, meaning it turns clockwise to remove and counter clockwise to install - the reverse of normal bolts.