SGII - I think the correction is at 12.6% and I haven't programmed any xgauges, I remember a little bit of FORTRAN programing.
Tire size = stock but the tread depth is 11/32 with a 23.6" OD and 880 rpm vs. 10/32 with 23.3" OD and 892 rpm = 1.01% difference. Now, that I think about it, my mpg from the stock tires should of been corrected due to less tread which would have yielded higher mpg readings.
Wind - website gave a graph of the wind speed vs time of day and a graph of wind direction at the time of day. So, I used the time of day and picked the corresponding values.