Traction Suitcase Weights - 2516 - Securing?

[2516mo]

I ordered suitcase weights to offset the mower I use for cutting the field. The weights fit pretty well on the bracket, and almost line up between the predrilled holes (which I would guess is for a brush guard, but they did not come with any securing bolts and nuts, like the user manual states should come with them. Any suggestions? Should I be concerned that the weights are not anchored and just hanging there, or should I try to rig up something on my own?

Thanks in advance!