Exhaust Manifold Question

[photograferz]

I have a 75 Spider. I have been in the process of replacing all of the front oil seals, hoses, water pump, timing belt etc.. and this cracked plate on the exhaust manifold was driving me crazy, so.. the exhaust manifold has an ovoid shaped plate with a ball/pipe fitting on top. The plate is cracked in half, so I decided to remove and repair. Upon removal, it just crumbled to pieces. Beneath the plate is a small reservoir that was filled with some type of powdery, crumbly substance. I vacuumed it out to see what I was dealing with. I have not found a hole or port, so I am not sure how to proceed. Do I fabricate a blanking plate and seal off? If I find a port can I weld it? Any guidance would be appreciated. By the way, all smog equipment has been removed.

[So Cal Mark]

that is the egr connection. If all of the emission equipment has been removed just block it off