I will suggest you use a fine rat tail file and file the ground surface until its completely square and flat.
I used a hand file and square to go over my grinder cut bushings when i had to cut some bushings down for a lift kit Control arm install that did on my old 4x4. I got them square by filing them by hand in a vice.
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Save gas
Ride a Mtn bike for errands exercise entertainment and outright fun
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