The stuck nylon is because you galled the threads (stainless is prone to that. CCuttingthe nut off is the solution. I had the same problem with the 5/16″ carriage bolts spinning in the 3/4″ hoholesThe solution for me was to lock visegrips onto the head of the bolt inside the trailer and then screw the nylon on until it drew the bolt down against the floor. The visegrips is put on the bolt head just at its lip and spins until it runs into the trailer wall. Why did you have to resort to hockey pucks? CLC sent me 1″thick Starboard discs, cnc cut and predrilled.