UO-8 hi-ten? I doubt it. I know the love here for UO-8s runs very deep, but my experience with my 1967 UO-8 suggests the frame was closer to mild steel. Every time I laid that bike down, even in otherwise completely inconsequential spills, it rode differently afterwards. I gave up trying to keep it aligned and just accepted it as a slinky. Maybe Peugeot changed the tubing later, but what I had was not hi-yield steel by any means.

Ben