I don't want to rebuild THAT engine as it has babbit bearings and everyone seems to agree that it would be a waste of effort, money, etc. I will repower the truck sometime but I have to find a good donor first and wait for the leaves to come out in the backyard - I am strictly a shade tree mechanic.
In the mean time I will try the various additives and synthetic oil and report back with my findings. The PO said he ran detergent oil and there is no crude on the stick, so it is worth a try.
Thanks for the comments.
Wilber