If your heading out htat way better to come out of London from Eltham then Sidcup and along the B2173 towards Swanley then just as you come to the traffic ligts on the edge of Sanley take a left and then a right towards Sutton at Home and on towards Longfield, avoid all of Dartford e.t.c
Nice idea Tommy, but there's nowhere to cross the Medway between Rochester and Leybourne. I'd rather go through Dartford than bloody Rochester!