Autometer EGT Probe Fitting Size

[No_Skillz]

I have to take out my EGT probe and mail it back. I've only had the guage for 1 month and it's shot already. Since I have to drive around w/o it for a while like that, anyone know what size fitting I need to plug up the hole in the exhaust manifold?

 

[No_Skillz]

Also, if someone could give me a heads up about material of the fitting (brass, aluminum, stainless steel, ect) that would work the best, that'd be cool too.

 

[idt512]

1/8 NPT plug, you'll probably want a steel plug since it flows 1000+ degrees through that manifold