The primary reason the pads are shaped the way they are and run in the direction they do is so that the soil will not build up in front of  the grouser, reducing traction. Most of the grousers on these older machines are relatively worn anyhow, so reversing the tracks really will have no adverse affect on the machine itself.
IN dry conditions you would notice no difference, but in clay-type soils it will become a pain in the butt.
............Cal