Note: Some, I say some, not all, have had to polish the spindle a little to get a new roller bearing to fit on but it seems to be the exception and not the rule so don't be afraid if you get a set and one of the bearings is to snug. Get some polishing paper and in a couple minutes you will have a nice neat tight fit. .....now you won't be surprised if it happens to you.
My technique: freeze the spindle, heat the bearing (not too hot, dummy!). Drops on then sets firmly.