I lusted after a fa300 twin for months,ended up with an fg57.
Since the engine is secondhand and you doubt your bearing condition i'd strip it,do the bearings gaskets o rings and seals it costs peanuts for peace of mind if you don't count your own time.Big reward tho when you first start it.I think sr telemaster owns one so if he reads this he may come along and o9ffer some good advice.For gawds sake don't let him talk you into a cdi conversion !
Fnq zero degrees c is no fun in the mornings man,the old 'f' scale sounds better at around 28f ?