If your engine is a 55282b it definitely was a ball bearing from the factory (1970 version roadster), It's possible the very early ones were bushing though if the number is different than above. Easiest way to tell though is simply look at the sidecover, I dont have any pics with the seal off but the engine on the left is Ball bearing and on the right is Bushing Just pop a hole in the seal wall and us a small prey tool to get it out and the clip is right there, Good set of snap ring pliers is all that needed.
Did have a photo on here of the shafts, you can see the groove for the clip