Does anyone have a good method for removing and re-inserting the bearings and bushing in the blade grips?

I have replaced my grips one other time before and got it to work by pushing them into the grip with a medium phillips screwdriver.

Last night I was replacing a grip and I couldnt get the bearings to push in by had so i tapped it with a hammer lightly and it blew up my bearing. Im wondering if there is a good "tool" to use for this purpose that wont destroy my replacement bearings that are on the way now

ANy help would be appreciated!

Greg