I bought a few "thick and strong" 2-inch SS fender washers to strengthen the post mounting on the lift arms.
(At 1/8 thickness, they might be a bit too thick for the one-inch post mounts and nut- but I can grind them a bit thinner in that case.) With 2 inches of total diameter, I intend to add 3-4 more bolts (more narrow) between the hex fitting of the mounting post and the perimeter of the fender washers.
These added through-bolts will provide more contact area with the thin lift arm sheet metal, helping to resist cutting and movement by the post mounting arm in the center. As long as the fender washers don't move, the mounting posts will be kept in proper position.
https://www.amazon.com/Stainless-Fen...dp/B08G1SYGDD/