Originally Posted by asw20c
Really? Seems to me if you rigidly attach an engine stand with a single degree of freedom (roll) at both ends of the aircraft and the axis of rotation does not accurately align and go through both, then you run the risk of tweaking/bending the fuselage. If you only attach an engine stand at one end, presumably at the firewall, and simply let the aft end rotate on an adjustable height table or saw horse, then I would agree with you that there isn't much thought that needs to go into how to align the rotation axis.
Although now that I think about it some more, you can have a single degree of freedom on one end, but you will need 3 degrees of freedom on the aft end, hence the offset attachment from the OP's photos.
Regarding the rigidity, I found that there was more than enough 'slop' in the shaft of the rotating head that allowed the fuselage to move up and down as required during rotation. The slop in the engine stand equated for about 6 inches of up and down free movement at the rear of the fuselage, which was more than enough to allow the fuselage to rotate unhindered.