A.I.R. pipe retaining bolt/exhaust manifold question

[MillerAPF84BII]

Hello, all. I am getting ready to put my fresh-back-from-the-machine-shop left side head back on the 2.8 in my '84 XLT. In the process, I have successfully removed the rusted-in-place headpipe studs, O2 sensor and broken-off stub of A.I.R. pipe at the back of the exhaust manifold. I've got the retaining bolt for the pipe drilled out almost to where I can start punching its remnants out of the hole. My question is this - does anybody know what diameter and pitch that particular bolt is? I'm going to remove the right head as well, just so I don't have an extra gasket laying around; not sure yet whether I'm going to try and restore everything to stock configuration or do the smog delete with the distributor and carburetor swaps, but I'd like to be ready for either... Thanks in advance - Chris

 

[MillerAPF84BII]

Got the right side manifold off yesterday, and got some of the threaded bits out. Used the pitch gauge at work to determine the retaining bolt for the A.I.R. pipe/check valve at the manifold is M8x1.25.