G'day Mark,fwiw,B series motors are generally pretty good,solid,mainly dependable,no probs with spares (if you need them),not too familiar with plunger rear beezers,later s/arms better,it's the earlier box too,M20/21 s/valves used them too, multi spring clutch was pretty awful,(but still works ok i guess),guess it depends on $ asked?,hths?,cheers Mick