If im decipering his post correctly, he is talking about the nipple on the back passenger side of the intake that one of the heater hoses connects too.
dont remember what the factory nipple is made out of, but my Dorman's nipple is plastic
Your best bet would be to replace the intake, might as well install a PI intake, just need to use a little copper RTV where the intake and heads dont line up properly.
i suppose you could cut the nipple off and either use a pipe plug and block it off, or use a metal nipple with a pipe thread on one end. but dont think it would work too well.
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