That will completely drain the clutch and transmission oil. Since you're going to have to take off the right side cover, I'd throw in new water pump seals (it has two, an oil seal and a water seal) while you've got it off.
The CRF was the first of the 3 or 4 Hinson baskets that I've done where it really was necessary to heat the new basket on the stove and cool the gear in the freezer to make it easier to put together.
I didn't get new ones (and I'm not sure if you can), but the rubber bumpers inside mine looked questionable. If possible, I would suggest replacing those while you are at it.