Another way to mount to racks similar to what you did with the safety wire is 120lb zip ties, they are kinda spendy though for zip ties. I have a small action packer mounted to my cyclerack with 6 of them. The math on that pretty much means the tote will obliterate before the ties let loose. Used some plates I found at the hardware store that have countersunk holes in them inside to reinforce the tote floor and I have the version of the rack with the turned up rear so two of the ties are back there with washers inside the tote to disperse the load a bit. Holds it tight to the back of the rack. Seat is a pain to remove though...... Planning to get a case like yours in the next few days, be better for trails being smaller just to carry some day supplies and I can strap my rubberized duffel to the top for camping and such. Tote is kinda big.