No Lift 360 Swap Tips/Suggestions

It does need to be a little wider at the back. Look thru the square tube the back wheels are bolted to and see if it's a clear shot all the way thru. If it is, measure it and see if a 4 x 4 will slide thru. If the 4 x 4 is slightly too big, rip it down on a table saw so it fits tight enough to have to be knocked thru with a big hammer, then bolt the wheels back to the bottom of the 4 x 4 at a wider stance. The weight is going to be mostly on the front legs anyway, so a PT 4 x 4 should be plenty strong enough to widen it in a pinch. A foot wider on each side should be plenty, but I'd want the 4 x 4 to be one solid piece with a few small lag screws ran thru the steel to hold it still.