[CC Rider]

There is a decent amount of room behind the water pump to work. 1/4 ratchet with a short 7/16 works great.

I've got one more idea to try.

Bill, I hope your Chevelle is nothing too serious. In addition to the water pump leaking, my alternator stopped charging last week too. Sent a correct core out to be restored and it is currently on its way westward.