Thanks gsJack! 

Went over to the garage today to shovel the snow away from the door after our record snow Fri and Sat.  While I was there I hung the front wheel of my 02 GS with blocks under the pipes with the bike on the centerstand and measured 5 3/4" from the lip of the wiper to the bottom of the lower triple clamp. 

GS specs have always reported 4.7" or 120 mm of front wheel travel so it looks like the forks could be slid up about 1" max to lower the front end the easy way if the bars are moved out of the way with risers.  Actually the 120 mm converts to 4.72" so maybe 3/4-7/8" max would be better.