I finally decided to rid my car of AIR and EGR. The onilne instructions said to get a 1 3/8" rubber freeze plug to fill the hole in the intake left by the EGR tube. I tried two autozones and Napa, nobody seems to have a 1 3/8" freeze plug, just 1 1/2" and 1 1/4"

The 1.5" plug will not fit. The 1.25" plug just fell in, and I tried tightening it down but as I turn the nut on top the whole plug turns....I managed to get it slightly tight by pushing down on the plug while turning the nut, but I just don't know if I can trust it not to leak. What did you guys do to keep everything left from leaking?