Wed - Just to get you a sense of pace. Warm up, 1-2 miles. You can do this either on a track or on the road. 2 X 800 @ Goal Marathon pace, with full recovery in between (until you feel like you are recovered, basically). This will not be fast or difficult at all, since it will be done at marathon pace (let's shoot for about 8:20 pace--what will you be shooting for??? I would side on the conservative side...for the first half of the race, at least. If you get through 18 mile and are feeling really good, then, by all means, do your worst to that pace. Beware the Heartbreak hill!!! 1 mile or so cool down after the pace.