I also had trouble with the Aresti wheel pants. I drilled the holes as per the instructions but could not get them to go on. I would recommend making a slot to allow the axel to slide up into the pant. The width of the slot should be just large enough for the threads. I used a thin metal washer instead of the wood plate. It was too thick to allow the nut to go all the way on. If I recall I had to move the pant up quite a bit from the location on the plan to keep them from dragging on the grass. I did not use the little screws for the pant, I just put some CA on and it has held so far.

Good luck, you will like this plane. It is a good flier.

Mitch