Wow, nice job Brian. For clock cases and boxes that will be terrific. I do have one suggestion. Use your engineers square to line up a vertical piece near one end. Without that reference, it will be easy to make a slightly off cut so your box won't go together perfectly. You also need to be careful to get your blade 90 to the table and preferably 45 to the sides of the jig. If the blade isn't 90 and 45, then you will have to be careful to number and match the ends in sequence. A 44 and 46 degree will meet at 90, but only if you match all the cuts so the two cuts are always paired. You will also have to make sure the two opposing sides are exactly the same length, and that the ends are cut square so the fit down into the slot completely. I do like this jig. Use a really nice crosscut blade and full kerf with it.