really because im pretty sure thats one of the main reasons things crack when they are welded and mudded over...because there not fully welded...seems like u already know what u want to do so why even ask the question?
i see many filler plates get tacked in the mudded over and never crack and thos are but welds this is tacked of a 1/4 gap with 3/4 over lap on each side sorry but it s not gonna crack