Put all new gaskets in it while you have it out too. I have a 49 4 speed (not sure if it's the same as 46) but anyway, i took mine apart and washed it in my parts washer, then used the blow gun to blow it dry and get all remaining particles off. Without a parts washer, i'd use a pressure washer on it. Taking just the shift tower off isn't a big deal at all- like i said before you should put all new gaskets in it anyway... they're cheap.
