I've gotten many tire beads on stiff tires that wont touch the sides of the rim,to seat using a bucket..one that has a big enough diameter so only the tire touches the bucket,and the rim is free to fit inside it..a 5 gallon pain is about the right size for most tractor tires,a garbage can can be used on larger tires like a car's..
You'll also need some type of round disc that fits in the center of the rim,to cover up the center hole,and lug nut holes.one not so large it'll cover the valve stem though--just the lug holes and center hole..you need to be able to add air!..
I find an old lid from a kitchen pan works good,and it has a handle..
I put some bead sealer,grease,or some other type of sealer around the rim beads first..and use liquid dish soap on the tire bead..
Place the tire & rim over the open end of the bucket,valve stem side facing up--then push down on the rim using the pan lid with the palm of your hand..press hard enough to force the upper bead against the rim,and apply the air chuck to the valve stem..
The tire will want to push against you,so hold pressure against it..the air trapped inside the bucket inflates the tire and pushes the bottom bead against the rim,and after a few attempts it usually pops into place...
I had to use this method when putting skinny tires on wider rims often over the years on my cars & trucks..
I've used starting fluid too,but mostly on things like large bucket loader tires and bigger dump trucks,tractor trailers.
I've seen one of those tires explode when too much was used,and I also knew a guy who was killed when one he tried inflating at a tire shop was in a hurry and didn't put the tire in the "cage" before inflating it..
He was blown 25 feet straight up into the steel building's roof,and actually tore a sheet of the roofing partly off,and he was suspended there hanging from it,it was a gory scene according to the witnesses...

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