U joint instillation problem

^^Answers above^^ Make ABSOLUTELY certain rollers are not stuck in bottom of cap. If not get the joint in, with one cap etc, press joint gently so uncapped journal is moved outward, then slip second cap on. Now you can install one snap ring, then press joint towards that direction of snap ring. If second ring will not go in, you have moved the yoke a little bit. With yoke still clamped in vise or press, use a large brass (soft) drift to move the errant yoke ear out a tiny bit. Joint should NOT be real tight when done so far as rotation. If so, "whack" each yoke ear from the outside and see if that loosens up joint