I'd recommend sending photos that show your current natural density and the density of the unit you are wearing in along with your order. This will give the factory a good visual reference to follow when creating and graduating your unit.

It would be extremely hard to specify a correct numerical density on an order form alone for a good match/blend in this situation.

I also agree with everyone else that going with an all lace or lace w/ poly sides unit would be your best choice... Getting rid of that poly in the front will make a world of difference!