Yeah, Ive seen the holes off a bit too.
With the racing props, several folks do what Swiss noted there... the counterbore in the back of the prop is properly tooled - and is on center. The shaft hole is not always exactly on center (2 piece tool or for some reason?) Who knows. But if you noticed it after consumption of refreshments, it is worth fixing
Anyway, the bushings work well. I think you can get prop bushings from Jett or from
www.darrolcady.com just make sure to get the 1/4" dia bushings - the ones for the Nelson are 5/16".
Or you can make them yourself.