Saprano Radius Top

I know that top radiusing has been covered in other posts but I haven't seen the answer to this question. I'm working from a Martin saprano plan and it does not indicate any radius to the top or the back, though the back is arched fore and aft. Should the top be radiused and if so, how? The only braces on the top are at the waist just below the sound hole and in the upper bout with only a bridge plate in the lower bout. It hardly seems that a bridge plate would hold a radius.

Ah but it does hold the radius... I have the Andes soprano plan and it does seem to indicate a flat top, which I just can't do. I use a 22' radius on my soprano tops and 12' on the back. I radius the lower waist bars on the radius dish and glue it and the bridge plate on the radius dish using go bars. Then the upper waist gets glued on flat, and yes the top holds its shape. Some say it's not needed to sand the bridge plate because it's so thin that it will conform, but I do leave it a bit thicker then sand a bit of the radius into it, even my wife asked me why I was doing it lol. When all is done I use a 120 grit piece of sandpaper taped to the top to shape the bridge to conform to the radius.

Although many rudimentary plans don't show it, it's not a bad idea to radius the top of any ukulele, in my opinion. It allows you to build the top a bit lighter while adding strength to the entire sound box. Many plans will show flat top construction for simplicity sake, while a radius top is considered to be a more advanced option.
Along with bracing, radiusing is largely determined by proper shaping of the sides. Meaning, in this particular case, the top of the bent sides must be sanded in a radius dish, much like the back is. That is what will maintain the radius you want south of the sound hole brace.

Thanks Vic and Chuck. It sounds like I can't put off making the radius board any longer.