I won't re-type the whole text so that thingiverse web site will lose it again... Remember: always Copy and Paste somewhere else before clicking "Save & View"... :(

Use 3/16 x 2" Long Nuts and bolts. Some bolts need to be shorter, but I used the same bolts everywhere and where is was sticking out a bit too much, I just cut them with a rotary tool.

https://youtu.be/mKJ6k-OwxNI

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Update 1.0:

You should use eyebolts instead of the top screws so you can attach them to the bumper with some chains to prevent the plow from tipping under when pushing the snow

Infill: 25%