How to Fit a tapered bushing

This stepper motor has a 1/2" shaft and I have to attached a tappered bushing to be able to mount the pulley on it.

However there no way the bushing will "slide onto the shaft" as the instructions say it will.

The bushing (Martin JA 1/2") has a 50 mil gap which lead me to believe it would a loose fit and "clamp" to the shaft
when I attached the pulley to the tapered bushing.

My Question: Is the user expect to ream out the pulley to fit ?

Any other tips on mounting this type of bushing and pulley(18L100 JA) would be very welcome.

Best regards
Hans W