1965 Dart 270 4dr sedan

Yesterday I recieved the exhaust system for my taxi. Looks great. Except one thing, the flange towards the manifold wasn't there. I took off the flange from the old pipe but what to do next? Should I just bolt it with a gasket and thats it or bolt it and then weld it in place?

20231102_204330.jpg

20231102_204317.jpg