Hiya Gary , I ran 3 marathons in 3 consecutive Sundays this year, Amsterdam, Frankfurt and Rutland Water, and also 2 marathons in 1 week.
I found the most important part of the recovery plan was to have post race massage immediately after crossing the finishing line, it made a huge difference. Then all the other recovery these: massage, physio, foam roller, cold bath, compression tights, yoga, pilates or Tai Chi.
I didn't run in between marathons, except for warmup run before the race.