Will it fit?

A short tail did not come out of a RR unless someone somehow adapted it there. Get the casting no's off the bell

SB bells are all over the map. If it is an earlier, AKA 273 bell, it will only accept a small clutch. If it is out of a pu or van, it will be a large flywheel. It might not fit the A833 pattern depending if it was out of a 3 speed, and there are issues with the center hole.