There is a $5 slave cylinder release tool, available at any decent auto parts store.
You can do it with a screwdriver, but I wouldn't recommend it for your first time.
A platform-style transmission jack is also highly advisible. Harbor Freight sells these, or you can usually rent them from tool rental shops (though they are often the very elaborate style -- usable, but inconvenient due to weight). The transmission isn't THAT heavy, but the jack helps move it around without wearing yourself out too badly. As long as you separate the transfer case (if you have one) first.
You MAY need an impact wrench to get the Y-pipe out, but living 1000 miles from the nearest salt truck, you're probably fine with some leverage (3/4 galvanized pipe works) and some Kroil.