The seal ID is usually going to be different. The determining factor is the Yoke OD. No worries though, if you're doing a swap and the seal isn't correct just measure the OD of the seal, the width of the seal and then the diameter of the yoke/flange you're going to use and then hit up a parts store and they can get you the proper seal using those dimensions.
Oh, if you're talking about the serrated seal that goes on the shaft after you've slid the yoke on those are different. They are either 30 spline serrated or 32 spline serrated.