Buy it and burn it...no need to wait. I didn't even take a wire brush to mine. I burned it, burned it again, and took the burner to it. If all of that didn't get it off, it wasn't coming off at 225.
Pitmaker BBQ Safe
UDS Ver 1.5, 90 gallon Super UDS
Beat-up, rusted-out, still-cooking NB Bandera
Some thing that says Brinkman on it