I didn't realize so many screw heads were buggered throughout, i did notice at least some of the valve cover screws appeared not to be, but i did not look that closely for any buggering on all of the screws.
The buggered heads you describe, Keith, certainly could suggest engine removal decades ago. Perhaps the owner put the bike away in the mid-70's, resulting from an earlier event requiring screw removal...... The bike apparently was still rideable, because he kept getting license plate tags for a couple years later...... Perhaps his widow would know. The screw heads do arouse suspicion, in turn, putting a damper on vigorous bidding.
Of the Honda rubber foot pegs i've seen, i seem to recall seeing some rubbers more degraded than others, some fairly decent bikes having degraded rubbers and some fairly rough bikes having pretty decent rubbers. Seems some rubbers were more plastic like and some were more rubber like. Makes me wonder the possibility of a particular batch of rubbers might have had a percentage of difference in the mixture which was run through the mold, or the heat in the molding process was slightly off..... Pure conjecture..........
i still believe the bike is largely original/correct and as you say, Keith, a nice specimen.