1991 GEO STORM ELECTRICAL DIAGNOSIS SERVICE MANUAL SUPPLEMENT - ORIGINAL - ST371-91EDM. This is the Manual that Supplements the 1991 GEO STORM Service manual. It covers ELECTRICAL DIAGNOSIS, WIRING DIAGRAMS, COMPONENT LOCATIONS AND DIAGNOSTIC CHARTS, ETC.. Measures 8 1/2" X 11". Used Condition from a GM Dealership. Will be packed with added protection and promptly shipped.