H-500,
I checked the spacing on my cowl and the blisters are evenly spaced, then I pulled the plan and sure enough, the template has the blisters grouped just like your cowl. I then took a look at my instruction manual, it only has 13 pages with no reference or photos of the cowl, just a simple drawing without blisters.
I'm not sure what the heck I've got, the box indicates that several versions of the WACO can be built but the plans only show the open or closed cockpit version. It also show the outline of the tail feathers on the closed cockpit which are considerably different than the YMF - 3 / 5.