The plan shows a 1/4″ plywood firewall. I think this is excessive for this size plane, and my laser cutter doesn’t like 1/4″ plywood anyway, so I’ve sized the fuselage doubler for a 1/8″ firewall.
Also, I like cap strips on my ribs, so I am offering ribs cut for cap strips and 1/16″ trailing edge sheeting on top and bottom of the trailing edge stick. You can choose this style of ribs or the standard ribs shown on the plan. The cap strip ribs will come with a 3/16 x 3/16 spar notch for a spruce or bass spar.
This plane flies equally well with either an OS 10 FP or 15 FP. It really is one of the best small sporty planes I’ve ever flown. It has an uncharacteristically flat glide for a plane its size. If you want a sporty plane that fits in your car, this is it. I can’t recommend it highly enough.