Bridge Crane to Gantry?

I am not kind to myself, having an enormous amount to do just having a major cleanup and then I make an impulse buy of more potentially useful stuff.
I spotted this on a local auction site and told a friend about it for a workshop he is building to house his excavator and tractors and he then forgot about it. Came down to the last two minutes and I threw a bid on then the war started. I have a very limited budget but calculated that I could eat porridge for a few weeks and pad the dogs steak with rice on the side so came up with a figure, bid and turned the computer off.
Got busy but when I checked a few days later found I'd won. In U.S. Dollars $100.06
It had been sitting in a yard for a couple of years and the trolley was seized up so I painted some Emertan rust converter around and next day followed it with some home-brew penetrating fluid. Came back a couple of hours later and less than 10 minutes with a bar had the trolley rolling freely by hand, made my day.
The penetrating fluid I mix up is 1:1:1 Kerosene: ATF: Diesel and as I was at the end of a bottle of semi-synthetic two-stroke oil I added some of that too, I think there is a noticeable difference. I'll have to tu-tu with it a bit but thinking that I'll keep the 1:1:1 ratio with the ATF,Diesel,and 2-stroke oil and up the Kerosene to 1.5 or 2 parts.

Although I would love to erect some rails and use it as a bridge crane over what is left of my driveway I am thinking converting it to a gantry crane would be quicker and cheaper as there ain't a lot of A45 crane rail going cheap at the local scrapyard.
Length is 2940 mm, width 1000, height 640 mm.

Attachment 39449
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Attachment 39451

Looks good, now the work begins. If'n it was mine, I'd consider removing the end cross pieces, rotate them 90°, weld them back on to widen the unit.

! Terrific deal. With limited headroom, a bridge is less than ideal.

I have eyes out for 5t span of about 30', with figuratively same general concept. If a gantry IS possible it will link heavier equipment, which are all in a line. They're wired by drop cords and connectors, no other impediments. The rail could be V-grooved wheels running on inverted angle iron to minimize trip hazard. Like most, a hand chain fall is preferred to electric, though I'd hang two for manipulating.

Katy, The end pieces are fabricated box section and wider would not be better where I live due to lack of space. Under the span is the same as the shed door and I could drive under it.

Toolmaker51, to reduce cost I am leaning towards a gantry. Thinking of bolting some uprights to the ends of the end truck and a friend has given me a 3T trolley so I can hang two hoists.
Now the search begins for some reasonably priced steel. Have to keep an eye on the auctions.