a lot of time s the front cross gets hammer by the road or lack there of and close up the front cross member and when you try to get the front end alignment back in there is no a justment all shim out. this is where the dent may came from rebending or opening it up. this done with a big I beam and a 20 ton bottle jack and the horns get chain to the beam and things will move . but what i would do is cut the plate out with cut off and drill out plug welds and get it out and hammer it flat or a new pice of steel and weld it back in i have work on many frame you can work the steel just like sheet steel just bigger hammers. if you dont feel you can weld if then dont do it and find someone that can weld good or just live with it