The shop floor is at least 8" above the outside.
The 300Kg lathe was lifted throughn the doorway, from the floor outside, and into the shop with the 1 ton folding engine crane. It was moved and rotated, with difficulty because of the restricted space, until the lathe could be lowered onto the bench, and fixings that awaited it.
Bench is ex warehouse staging, so quite rigid..
It was hung by a long 1 ton sling. The ends were around each end of a 1 " bar through a hole under the headstock with the bight of the sling under the Tailstock end of the bed. Tailstock and Saddle were positioned to give the best balance. Care was taken that the sling did not bend the feed shaft or leadscrew.
(The operator manual suggested using a hook clamped tom the bed, using Saddle and Tailstock to get a level balance. )
My WARCO Economy Mill/Drill was positioned using the 1 ton folding crane, again through the doorway, but from outside this time.. Short 1 ton sling around the head, keeping centre of gravity as low as possible.. Crane poked it through the doorway, to be lowered onto the steel bench.
Once it was bolted onto the bench, (on an angle iron frame to spread the load on the floor), levered the bench up at each end and inserted 1/2" steel bar as rollers. Put 4 x 2 across door way and used a car scissor jack, and pieces of packing to push bench to the far end of the, admittedly small, shop.
Howard