tiger moth another Dumas

I have a large Dancing wings Tiger that's on hold at the moment. When I started to cut film for the fuselage I noticed that there's a stringer that runs down each side from the engine bay almost to the tail empenage. I think it was to stop the fabric covering from flapping against the main fuselage. I can't find and don't have a size for them. Is there any indication of their presence on your plan?
 
You can see it clearly here, it runs from the step behind the engine cowl through the 'ZS'
Why anybody would want such a high gloss on a Tiger I can't imagine, money to burn I suppose.

Fuselage stiffening? Anti-starved-horse frames?
Lovely lightning bolt captured between the starboard wings, off in the distance!
High gloss finish  perhaps an air-show special, rather than a daily work-horse?
It is clearly visible in this photo of a camo one -
www.recoverycurios.com/de-havilland-tiger-moth

Ah, dog walking, excellent lubricant for the grey cells, Mary and I walk ours twice a day. We lost our old Jack Russel (Chien) last Sunday, she must have been at least 20. Took her last walk with us, had to be carried the last 50 yards, refused supper, went to sleep in her bed, never to wake up, still hurting.
I note the side stringers are 1/16". If I could have the exact width of the fuselage without the side stringers I could scale up to find the size I need.