Here is my solution in the new shop
While building the shop, I encapsulated half of the I beam inside the reinforced concrete (not US, so different construction methods). The I beams run in parallel through complete width of the shop, while parts of I beam encapsulated in conrete are welded to rebar.
Two trolleys, rated at 1 ton each hold the transversal I beam on which an additional trolley is mounted, together with electric hoist rated at 800lbs single line or 1600lbs double line.
I think it definitely beats the unistrut solution few posts higher.
It started like this
And it currently looks like this: