For me it is quite complex this kind of situation because the area I am trying to cover is the market which has a very high density, the width of this area is 700m and 500m which is a very small area so I have put some microcells within this area which was previously covered by two Macrocells. so this sites will be an underlay for that Macrocels(overlay/umbrella).If have Google Earth on your PC I can send the file to you and open it with Google earth so you can see the where the macros and micros are within the polygon which covers the market. If you don’t mind please send me your email to abdi.muse@yahoo.com so I can send you the google earth file. Thanks