Problems patching a 1/4 panel

How much have you gotten done so far? If you've just tacked it in there with no real strong welds, cut the tacks and pull it back out. That'll give you some room to do some metal shaping. If you've got something more solid going on might not be a bad idea to take the cut off wheel to it and do it again.

You're using .030" wire? Go slow. Don't rush. Allow the tacks and the metal to cool almost completely before moving on. Run a bead at one end, go to the other, come back to the middle, then back and forth. Slowly.

I do have to ask the question, though, if you're using gas, why are you using .030"? .024" is half the price and easier to work with on thinner gauge sheetmetal.