Whether torque-to-yield or not, I still wouldn't use 68-year-old rod bolts. Before going that route, and risk spinning a bearing/throwing a rod, I would buy a new set of rods.
I think Ron has dealt with John Mummert (ford-y-block.com) and is probably aware that he does have H-beam rods that include new fasteners. They aren't cheap at about $500 for a set, but if built right, he should have considerably more invested in his engine than that. Sometimes you either pay now or pay later.
Try contacting either Tim McMaster or Ted Eaton, either of whom might have a more affordable (and safer) solution than reusing old rod bolts.