What are the firebox dimensions for this and the 42?

Per page 9 of the Instruction Manual the 36 inch Sovereign firebox is 36" W x 37 3/4" H x 22 3/4" D. The 42 inch is 42" W x 37 3/4" H x 22 3/4" D. If you have any further questions please feel free to give us a call! Thanks.