Beech 18 Dimensions Needed

I’m hoping to build a Beech 18 cockpit, (SNB-5 to be precise). I’ve found a plan view but don’t know exact dimensions, can anyone help…Phil or Ben? I know I should use 13mm marine ply. can’t seem to get an image loaded here at the mo…will try again soon…

I am very slowly collecting original parts as well; there’s more info on my website if you’re interested.

Thanks in advance.