I am thinking the bearings go in in a certain order, it is like a taper, each one may be a few thousanth smaller etc. I am thinking large to small, front to rear, if on is in a wrong place, it my feel like a "tight fit' like say bearing number five is in bearing number three's place.
I know what you mean Dartswinger 70, he's been doing it for a while. But everyone makes a mistake once in a while. I hope it's just right and not in the wrong order.