Not fun, not easy, but doable.

My Problem

laptop was overheating

My Fix

The repair went fine. Someone suggested setting aside 2 or 3 hours. I was able to do mine in 15 minutes. Your mileage may vary.

My Advice

The best suggestion is already posted: Use a pill box or a large sheet of paper and number the screws taken out for each step. You'll never remember otherwise.

Also watch the plastic retaining clips along the right-hand side of the laptop after lifting off the keyboard. They are just "floating" there and can come loose very easily.