Looking great so far. Used the book on mine and it worked out great for me too.
A few pointers. On that control panel, you need to move the spinner and 4way away from the center. You will end up smashing your fingers on golden tee. Also, you might think about getting rid of the middle mouse button and spreading out the left and right.
For your monitor, get a tv. Search craigslist every day until you find a 27" with component input. That will give you probably the closest thing to an actual arcade monitor for $100.
Otherwise, keep up the good work and keep taking pictures. You really only need one more weekend to finish the construction, then comes artwork, setting up your computer, choosing a frontend, setting up your emulators, testing it, playing it, making changes, repeat.