X4 What everyone else said..
Recently, I replaced all three donuts and busted the last bolt I took off. It was a pain getting it out without damaging the manifold.. Although, I was really surprised how easy it was to take off the exhaust manifold on my V8.. minutes..
Be careful using using a torch after you used PB Blaster... You don't want your engine bay to catch on fire if you over sprayed it... Don't ask how I know..
Elias