If the pitman arm doesn't bind--which it probably won't if it had been driven like that----it willprovide OK service but my greatest concern would be that attachment and I would make darn sure that the mounting bolts have secure fit-even to the extent that they might be through-bolted right through the frame. And a reinforcing plate could be used on the nut side to insure there would be no warping. Steering boxes coming off the frame must be one of the most threatening breakdowns. Certainly a qualified hot-rodder friend could help. ( and what the others have said.)

Best wishes for a safe repair.

Sparky