I flip the all the time at work. The only hard thing that you have to do is weld the perches on the top of the axle instead of the bottom. DONT just flip them. The axle is pre stressed (curve in the middle). Plus if you flip them the brakes will be upside down and wont work well at all. .... and the left and right brake setups have to be on the correct side.....
here are a couple of pics of my bosses.....
