A 3-jaw puller may be able to pull the bearing off, You will need to find someone to press the new bearing on...or side a pipe down the input and hit it on. I personally wouldn't do it this way as you risk damaging the input shaft.
WHen you put it all back together, make sure you get 0.000" of endplay, but don't let it have interference. If you push/pull the input and output shaft together, there should be no play. If it was shimmed properly when you started, it should be fine, but just something to check.
Also, make sure you don't loose the roller bearings inside the tranny. Use petroleum jelly to hold them all in place when you put it in.