I agree with Bob, moving large heaby machinery can be done very efectively using the Egyptian roller method. Keepint the C of G as low as possible provides a degree of safety.
My Ajax AJT4 which weighs in at around 1.5 tonne was moved using lengths of 1″ solid round bar, I would not recommend using gas or similar pipe due to the potential for distortion. The machine in its original guise is around 87″ (2210mm) from the base to the top of the motor which I think is similar in height to a bridgeport. It barely cleared under the up and over garage door but once in had sufficient clearance to the roof trusses. even now after adding a 7″ column spacer there is still a couple of inches from the top of the motor to the roof beams> To allow access to the air drawbar motor and facilitate drawbar removal, I have framed out the roof in the area above the mill and made a removable panel, similar to a loft hatch.