its not screwed in. Just pull it out as hard as you can.
you remove the front differential and the trans. should come right out
you dont have to but it makes it a lot easier.
You add fluid at the same place you check it.
Big job. A lot more work than it is worth, you will need to change the brake pedal, Remove the clutch pedal, master cylinder and slave, trans mounts may be different, center console, flexplate and...
if you have to ask. dont attempt it... transmission rebuilds are monsterously hard.