I have removed the seized exhaust studs and broken EGR tube fitting on the exhaust manifold with a lot of patience and heat cycles with the oxy/acetylene torch. I will not be using the EGR valve and would like to thread a sealing plug into the manifold. The thread size on the fitting does not look like a common thread size. Any suggestions before sending the manifold to get bead blasted and then I will be priming and painting it with the VHT exhaust paint. EGR block off plates are easy to fi