I just looked it up, Joe. The conversion plate sells for $26.99, jobber's cost, and can be used by rebuilders to convert those oddball manifolds to fit heads with regular bolt spacing. Goodson is a little picky about selling to private purchasers, but any automotive machine shop should be able to order their items for you.
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!