Some 235's have a 1/2" pipe thread in the intake just below the carburetor flange, bushed down to a 1/4" vacuum line for wipers. It's simple to install a bigger fitting to supply the vacuum if you have that setup. If the manifold is not drilled and tapped for the big pipe fitting, either enlarge the hole and rethread, of find another intake with the big hole already there. I'd reccomend removing the manifold before the drill/tap operation to keep metal shavings out of the intake!
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
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