I decided not to grind the welds on the battery box and make it look pretty. The box is made from .062 sheet, the fender well is from .042-.030 depending on where you measure because of the uneven thickness from the stamping process. Welding the air box with .032 wire (mig) I was constantly blowing holes and having to back fill . It was a fiasco. On the battery box I used .023 wire.
I'd rather have strong welds for that 54 pound battery.