My RE skoolie is 7'6" wide 6'6" tall. This
is a good starting point for paper doodles.The length you require can be found from there.
Some shuttles haven't any rear wheel wells and can be taller and/or wider than a school bus. Yet some are only van-wide, neck-kinkers. The specifics will come once youve narrowed your selection to a specific year, make, model, and winning bid. Still, they are factorty built to end user specs.
Penetrating between the seams, beam anchor points, alignment with the windows, the vehicles peripherals underneath, the axle placement, emergency exits. Every measurement WILL change with these factors.
Will you be constructing your bus at your home or your business?