@lkldpl Sorry for the late reply I have been unavailable.
I made my own gantry crane, and also designed and fabricated the joist crane. I m trained in structures, and had the gantry checked out by another Engineer using FEA. I have also moved 9 or 10 mills and even more lathes (mostly for other people) I have over 35 years rigging experience, and my father was a professional rigger in steel mills, and gave be a bunch of pointers before he passed.
Don't underestimate the complexity of such a move. I spent 3 months planning the move, one month installing the necessary equipment and lining up labour. The move took one day, as the winching firm was charging 80$ per hour. I had 9 volunteers helping, with specific instructions for each person... One individual was there solely to be a safety officer, ready to call STOP if anything at all looked of, or someone was not where they were supposed to be. There were 3 stops that day, all for minor things.
We cut a hole in the side of his house for the winch cable, and reinforced the stairway, as the biggest piece - the Bridgeport base - weighed 995lbs. All the machines were broken down into manageable pieces and placed on custom built moving dollies. (every piece was weighed on a crane scale before being strapped to its dolly)
The stairs got 2X8 on flat on either side, so there was only about 10" of walking space in the middle. Once a piece got to the top of the stairs, they had to be turned 90 degrees, and then out the door - on to a temporary landing outside the door. (The doorway was 8" above the concrete patio).
3 professional rigging firms refused to bid on the job, citing safety concerns. one wanted 10,000$ for just the Bridgeport mill taken to the back yard.
In the 9 hour move, all things went exactly to plan. not one inch of movement was unexpected or out of the planned envelope.
--- I should add that I helped move most of the equipment down the stairs - 45 years ago. Down is much easier than up.
Reach out to me on DM and we can talk by phone, and I'll try to answer any questions you have.