Starter
Disconnect the battery before you start.
You can replace the starter without removing the exhaust manifold, using extensions and a universal, 13mm socket (I think). It can be done but its a tough job.
I prefer to remove the exhaust manifold. Then remove the starter.
Do NOT buy a $50.00 starter on EBay, you're much better off buying a used starter, or rebuilding your own starter. I prefer rebuilding the one you have. A rebuild kit is about $30.00.
Lou