It is doable with the engine fitted but not as easy as on other engines because, as said, the oil ladder has to be removed to access the bearings and the 10 cylinder head bolts are screwed into it. The crankshaft is held in position by its bearing ladder so it won't fall out if the oil ladder is removed. However, on some engines it may not be possible to turn the crankshaft with the cylinder head bolts undone which is summit else to consider.