You can do it but thrust loads on the piston become unbalanced and may cause scuffing of the skirt after high mileage, mechanically the balance is affected slightly. There is virtually no chance of catastrophic failure due to this mod, at one time turning pistons around was a rodding trick used by many racers because it changes piston dwell before and after TDC. It has very little effect though and fell out of favor because of this.
“She may not look like much, but she's got it where it counts, kid. I've made a lot of special modifications myself.”
— Han Solo