For a drain/ filter change/ refill takes between 7-9 quarts. Just buy 9 or 10 and return what you dont use.
You have 2 filters in there. A flat filter for the sump, and a spin on for the cooler. Make sure to change the gaskets on both, and make sure they are seated correctly or your truck will stall when moving at low RPM. Be careful when removing gaskets and cleaning old gasket material off of pan as this transmission is aluminum. Dont believe the "cold" markings on the dip stick. It will say full cold, but you are actually a quart or so low, drive it and check it hot and forget there is even cold markings. Have fun, and lots of oil dry or rags as there is no drain plug on the pans.
Sure it'll suck, but it'll make you a man