Notes
Wed - Run of 6-8 miles. Again, keep it easy and just get in the miles
Thurs - Off or tempo run. Warm up for 15 min, then run your marathon goal pace for 30 min @ 8 min/mile intensity or pace (pace will be difficult to determine unless you have mile splits or a gps or something.) This should be your goal pace for the marathon (I assume). Remember that 30 min of marathon pace work should not be too difficult, but, then again, it shouldn't bee too easy either. 15-20 min cool down afterwards.
Fri - If you took yesterday off, do the workout today. If you did the workout yesterday, take today off. If you want to put in few miles and be an overachiever, by all means, go right ahead!