Wanting to replace both a terminally dysfunctional radiator and a rust infested fuel tank on my NAA, I first had to remove its Wagner WM4 loader. This involved removing the nuts on the four carriage bolts holding at the rear axle which were theoretically prevented from turning by the square holes in the axle casting.The all spun of course despite all my efforts including Vise-Grips attempts, cutting screwdriver slots in the heads, grinding flats on the heads, heat, etc. I eventually was able to defeat them but it took so long and involved so many combinations of methods I can't recall what actually worked. Thinking my struggle was over I removed the radiator whose carriage bolt square holes miraculously held on to their bolts but am now struggling with the single forward bolt on the fuel tank. It's particularly tough to get any tool on the round head or trying to help the retaining slot perform it's job of keeping it from spinning. I would welcome any advice on both general methods for keeping these bolts from turning when the square hole or slot fails or the particular problem of that single forward bolt on the fuel tank.