IMHO, based on my small 2T chain hoist, you'll have four issues:
These hoists don't have much strength, maybe 5T max on the one depicted.
Using one horizontally instead of vertically may be hard as the chains will want to drop off the pulleys (they're loose-fitting and depend on gravity to hold them in place).
You'll have to do a lot of pulling on that chain, as they've got a huge gear reduction inside between the hand-chain and the main chain.
Most of these hoists only move 8-15 feet at a time, not 300+ feet of a SRW.
I have my chain hoist that I use on the davit crane in my M1081. Lifting/lowering an 800lb bale of hay was easy but I was dragging that hand-chain a lot just to get a little motion from the main lift chain. Gear reduction.
Probably better to get an electric winch, but watch the duty cycle. Electrics tend to heat quickly and require lots of time to cool between pulls.
I was perusing all the stuff on Eastern Surplus, and came across this "basic issue" kit which includes a chain hoist. I don't ever remember seeing those in Army, but hey, do they work as a winch? Anyone use one that way?
https://www.easternsurplus.net/PartDetails/7298/ALL-5229-Partial-BII-for-Military-Vehicles
