If you will go to the link I listed above , you can get a small amout of info about the 1933 R-2 w/ flaps. They put the engine from the '31 R-1 into it, added flaps, and changed the shape of the rudder.
Go down the left side , and click on the "Gee Bee Super Sportsters"link. There is a good 3-view showing the cowl and rudder shapes.
If you add flaps, you need to change the whole look of the aircraft. Might be a neet , and differant model.