Hello and good morning mgraham112,
I want to welcome you as the newest resident member of the "Flail Mower Nations" from the Great State of North Carolina.
The fasted way to put gauge wheels on your flail crop shredder is to buy them from MCMASTER-CARR and have a welding shop fab up a mounting plate with a stub shaft welded to the plate for the stub shaft mount. You can have the welding shop drill a hole for a spring clip to hold flat washers in place to set the gauge of the wheels meaning stacking 1, 2, 3, or more washers under the sleeve bolted to the tube steel frame. You would leave one or more washers on the mounting plate to help keep the stub shaft from bending.
The 8 inch pneumatic caster wheels are the ones I think you need but you need to measure the height of the steel mounting point from the bottom of the tube to the ground.
The inventory number for these 8" casters is #22925T712 each pneumatic caster is $47.90+tax and shipping.
I am not sure if agrisupply would have a comparable flat free rotary cutter tire and stub shaft mount but it would be worth checking on.
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Hello and good morning Terry,
the rear swivel caster wheels keep the flail mower level at all times to maintain a level plane while shredding/slicing crops/brush on uneven ground. They are especially helpful when you are shredding crops that are planted on ridges/hills like peanut vines, potato vines, sugar cane stubble, pineapple stubble, agave, sugar beet tops , corn stubble, cotton stubble, pea vines, soybeans etc.