With a little creative plumbing, you can join the two ports with plain old 1/2" black water pipe (Don't use galvanized!) or brass pipe nipples. Another option would be 1/2" hard copper pipe, which has a 5/8" outside diameter, and is available at any hardware store, along with a variety of fittings for both ends.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!