I don't mean anything bad by this, but really...you can't figure out how to cut 6 rectangles out of a sheet of plywood?
Take a piece of paper and using the dimensions from the plans, cut out the pieces from a sheet of paper (to scale...like 1 inch = 1 foot so a 4 inch x 8 inch piece of paper = a 4 foot x 8 foot sheet of plywood). Then reassemble them on a 4" x 8" sheet of paper to see how they best fit. Use the leftover for cutting out bracing. Use actual plywood, not the paper, for the cab build though.
