I recently purchased the attached '76 super mirage frame. It had a 1" seat post jammed into the seat tube which after much effort I was able to extract. The frame is 1020 lugged steel. The 1" post (I measured with calipers) slices easily into the first couple of inches (roughly the depthe of the lug) but then it binds. With my finger I can feel an extremely slight lip at that point. I am thinking that I need a 25mm post which would be 0.4mm less than a one inch. Does anyone know if that is right before I order one. Thanks.