But...did you grind enough?
Turn the wheels to the stop. Mark where the lip on the LCA is close-to or touching the wheel. Measure 2" in on the LCA & grind to there. Do both sides of the arms.
That extra is for clearance as the suspension cycles.
All that needs to be removed from the LCA is that upturned gutter along the edge.
Make a nice smooth transition from the removed to what's left.
Both of my trucks had/have been done like this for years (decades!) & neither have had any probs with bending nor cracking. If there was to be any, it would of become apparent long ago, just due to my (*ahem!*) somewhat enthusiastic driving tendencies.
My '97 needed the arms done with 17's, even just at 2/4. (spindles)