Wouldn’t recommend a bolt-on receiver for the
burro. My bumper is simply u-channel welded in 2 spots. If you do plan to do this, I would recommend something beefier that bolts and welds to the frame below, not just the bumper. I did this for some bikes with an unused trailer hitch kit for a car and a bit of cutting and welding.
Also adding that much
weight and sway to the back means you need to be extremely careful with
weight distribution.