The dimensions (27.5x15.125x11.75) given in the guide are said to all be outside. Im just checking, does the 11.75 vertical include the top and bottom boards and does the 15.125 inlude the side boards?

You can't go strictly by the dimensions in the guide for the box size. They are for the specific box that brain built, but are one of the dimensions that will be slightly variable for each pj. It is important that you do not go strictly by those numbers. Your actual size will vary a little depending on the LCD you use, and the way you decide to frame it and the lenses. Once they are framed, you can then figure out the needed height and width. The length can be more standard. Just make sure you have room for your reflector, and the proper distances from light to fresnels, and frenels to lens. Good Luck!

Yeah, thanks. I'm probably going to go a bit taller than the one in the guide, I need the extra room for air flow. I'm going to start the building process tomorrow.

Make sure your LCD/LCD frame seal to the top and bottom of your pj, or you ariflow will not be correct.