You would be better off just leaving the stone flat and doing it Tony B. The problem you would have mainly is keeping a constant eye on it as they cook very quick and you really wouldn't be wanting to close the lid on the KK- or at least that is what I think. I don't actually use my tandoor for naan. I think it is too small as the naan would be too close to the coals. In restaurants they are able to regulate them far easier in very large gas tandoors. Charcoal tandoors are more traditional but the heat regulation is much harder unless it is very big. I use mine on very high heat for meats and fish mainly- but the flavours are amazing for that.
You can make good naan at home in a pan but a pizza oven is great.
Instead of naan you might also consider making bazlama in a pan and then brushing with ghee to finish? It is a turkish style naan and actually I kind of prefer them.