If you do the rebuild yourself, and this is your first time rebuilding an engine, plan on taking a long time. Don't give yourself any deadlines, because then you will be tempted to cut corners. If you dissassemble the engine yourself, label everything -- like which pistons went in which cylinder and what it's orientation was in the cylinder. Keep the rods attatched to the pistons. Bring it all to the machine shop along with the crank, intermediate shaft, and the head.
Also, it's worth it to ask around and find the best machine shop you can. If you have the shop mic everything for you, the only special tool you'll need to reassemble the engine is a ring compressor (and a ring expander if you use your old pistons and don't get new ones with the rings already in place).