Rc4wd end loader wheels

[Bruski]

So I have been reading the forums for a while and learning a lot. My question is my end loader, how do I get the wheels off? I see the little bolts and guessing that is what need to come off but what size socket do I need?

I need to take them off so I can take the rear weights off so I can put lights in them. Mother fasteners in the wheel well need to come out but just can't get in there with the wheels on

Thanks in advance