I am in the process of removing the 37 Chevy PU 216 engine and found that the one side of the exhaust manifold is broken where the exhaust pipe bolts on. The casting number is GM 2 838397. I located an exhaust manifold on eBay with the casting number of GM 7 838397.
Does anyone know if these are interchangeable?

I believe that the only difference between your broken manifold and the one offered on eBay is the casting mold number. Yours is from #2, and the eBay one is from #7. Otherwise, they should be identical parts and fully interchangeable.

Thanks, It is on a stress point, but do you think it is possible to weld the broken peice back on?