It sounds like the shoulder bolts on the hinge arms might be completely worn out, or maybe they're not even shoulder bolts. You might check those to be sure they're not worn or are the incorrect bolts.
Thanks for recommending that I check the shoulder bolts. Whoever did the resto job on this truck didn't install shoulder bolts, they just used regular 5/16 bolts with no shoulder - so there was excessive movement between the hinge arms and the bolts they used to attach to the hood. After installing a proper set of shoulder bolts, the hood lines up much better now. I still need to perform the alignment procedure, but I feel confident I will be able to achieve good results now that I've addressed the problem of incorrect bolts being used.
