How to fix my split trailing arm...or should I replace?

[Tx Firefighter]

It's not rigging them together. They were welded from the factory. Bridges and skyscrapers are welded. Pipelines and submarines are welded. There is nothing sketchy about a good weld.

Clamp the two halves together tightly, check it for straightness and have your neighbor do his thing. What possible justification is there for buying a new arm in this case ?