My first thought is that yeah it should fit. Then I saw the note on Rob's drawing saying that he recommends an AB 763 Pro chassis. According to the FAFG the cabinet width difference between a Pro and a Princeton is a full 8". Do you know the length of the board?
If you're getting a custom chassis bent and drilled then you could almost surely cut down on the size but depending on the measurements it may not reduce all the way down to Princeton size but looks like it could get close. That would of course also require a custom sized cab.