The bottom bolt is only accessable to very small female mechanics with tiny hands or German elves.

Before you replace... take a close look at the top bushing. On mine I did a "fix" by putting a couple of 1/8" dia. 5/8" i.d. o-rings on each side. So far it's been a couple of months of silence. Cost of "repair"... $0.26 and 5 minutes... priceless.