Best way to separate pinch welds

I'll have to check that out. I was actually wondering about that, swap the wheel wells and all/ all at once even though the original ones are fine.
Just like the reason I left them while as I got them for now til I'm ready for that part of the project as I am afraid of how flimsy the outer panel may be when not supported, because of it's length. I was gonna wait til I was just ready to do the actual swap to seperate them.