Get recovered and then follow your planned taper - 3 weeks out your main aim is to get to the start line healthy. You don't need the mental confidence boost and doing a long run 2 weeks out you won't see the benefit of that in endurance terms before the marathon. You've got some long runs in and having done one before you know what to expect - might not hit your target time but that depends what that was anyway. Good luck!
Local races my aim is to finish ahead of 1st lady as that is about the pace I aim at. Bigger races not so much - although London I was ahead of 99% . Local races anyone who gets past and stays ahead gets encouragement and a well done. It is racing after all so whoever is around me I will try and beat.