I've looked at mine and I don't see how you could just turn it around the other way. There is a little "jog" on one side of the pan at the rail and the other side is pretty much straight.
I was thinking about doing exactly what Bubba said, but there's not much meat at the one end to be cutting it and reversing it. And yeah, Bubba, the 49 through 53's are just about identical in the front suspension/crossmember area and I imagine the 54 is real close. My 55 is a little different but still would definitely need a rear sump pan.
Mike