The photo on the box, and the red decal set suggest the later model 1/5. BUT, his previous ad for that airplane shows another label, which looks more like the 1/6 label (but it's hard to tell because the forum software won't let you enlarge expired ad photos - go figure).
picca waco biplane kit new in the box - RCU Forums
But, in any event, confidence is very low...
Mike