Thanks DL for stepping in, I now see what Ken was referring to, and the problem with the configuration during the hewing process.
Ken could you give me an idea just how long these crucks are?, and the sizes of both ends.
It sounds like hewing a number of these for a rconstruction, repair or new project would be quite an undertaking--but be sure there is a way, just have to figure it out.
I suspect that there was a special set up for supporting them which had evolved during the 100's of years they were used, then forgotten about or discarded
I have run into just such problems especially in the historical processes of putting up timberframes, it is extremely hard to backtrack on technology,it is like learning in reverse, you are also working with a group of men who like yourself have their minds modernized
Your problem if I was given it probably would be done in this manner--with the bow down and the heavy end more or less close to the ground (supported) and the lighter end elevated coming to its natural position according to where and how the cruck is turned, I probably would then lay on a line and begin to flattend one surface--using a combination of axe work and adzes and if possible the broadaxe--having completed that side I would roll it over and after lining again would lay the cruck flat, (maybe elevating the ends, to come in line with a good working posture) and proceed with adzes and chopping axes and if possible the finishing touches of the broadaxe,--(this new angle though means that everyone is working in reverse, like right to left, which goes for example the right or left broadaxe, as well as workers who work right or left--some could work both hands)
I suspect that you are looking for a broadaxe finish, but maybe not, sometimes hewing and adzing finishes are hard to determine, especially in historic times.
It could be very possible that an adze finish would have been applied after the rough hewing, a careful examination of the old surfaces would be in order--I belive you know what I mean and what marks to look for--
I do believe that obtaining the proper angle to work on these crucks was the key, only now a little experimentation might be needed,-- a slight repositioning of the cruck during the flattening process might be required to keep this angle correct for the workers
I hope this might help you out, and thanks again for bringing this old problem to our attenion, it makes me think deeply again and reach into my bag of past experiences,