I have never done it but, I wouldn't hesitate to open the roof, remove/replace the bad wood and reseal the roof.
However, I did a lot of home remodeling, building and repairs in the past.
It's all in what you're comfortable attempting.
Maybe you could rent a large garage or storage unit for a week or short term? And get a friend to help?
You wouldn't have to worry about rain if you needed to leave the roof open for a day or so while you waited for materials.
Get some estimates to have it repaired. Then decide if it's worth attempting yourself.
Now if it was my computer that needed repaired, I would drive over it with my truck and then buy a new one. :)
What's your comfort level?