If you follow the instructions with the kit, the bolts go up from under the board. However the nut barely has enough room to fit next to the power jack and definitely doesn’t have enough room to rotate. Adafruit suggested turning the bolt to tighten it – somebody else may be able to get that to work but I couldn’t due to having the second nut which also needs to be tightened.
So you can invert the bolt – then the head fits nicely next to the power jack and it’s easy to tighten everything well.
Now you will have to snip the bolt to be shorter than the rubber feet. They are almost the same height so you may need to remove the nut before cutting.
Additionally, I had to snip the soldered power jack lead below the PCB because it was longer than the spacer nut. I guess it should probably be desoldered before snipping but I was too lazy and not confident enough for that.
Everything fits now. Hopefully adafruit will update the package for future orders. They never answered my question on the forum about updating it so I’m doubtful.