David Nelson, a former San Francisco State All-American, passed away on Friday, June 23.  Mr. Nelson had been battling Lou Gehrig's disease for two years.      David Nelson was an outstanding supporter of the wrestling team here at SFSU, Said San Francisco State Wrestling coach Lars Jensen.  "He served the program as a wrestler, coach and faithful friend for over 20 years.  He will be sorely missed."    Mr. Nelson had an outstanding year in 1976-77 for the Gators at 134-LBS.  He was 21-7, won the Far Western Conference Championship and placed 5th at the NCAA Division II National Championship to earn All-American honors.  Following graduation, Nelson continued to help out SFSU as an assistant coach from 1977 81 while continuing to wrestle.  Nelson was a three time Greco-Roman place winner at the U.S. Nationals and won a Bronze at the 1988 Greco-Roman World Cup.  In recognition of his continued support of SFSU wrestling, the Dave Nelson Outstanding Contribution Award is given each year to the wrestler who has made the biggest contribution to the team.    Mr. Nelson left San Francisco State in the fall of 1981 to teach history and health at Willis Jepson Junior High in Vacaville.  He was an assistant coach for the varsity wrestling team at Vacaville High School serving under his father, Larry Nelson.  David took over the head position in 1993 and remained there until he resigned in January, 2000.  While there, Mr. Nelson helped the team to 11 league championships, 10 sub-section championships, five section dual meet titles and six section tournament titles.    Visitation will be Tuesday, June 27, at St. Mary's Catholic Church in Vacaville from 5 p.m. to 8 p.m.  A rosary will be recited at 7 p.m.  A funeral mass will be held on Wednesday, June 28, at 10 a.m., also at St. Mary's Catholic Church.  The church is located at 350 Stinson Avenue.    Mr. Nelson is survived by his parents, Lawrence and Elizabeth of Vacaville; sister, Karen of Vacaville; sister and brother-in-law Rebecca and Sam McInnis of Vacaville; brother, James of Vacaville; loving friend, Yvonne Sooy of Vacaville; and two nieces and two nephews.     In lieu of flowers, the family requests memorial contributions be made to the Vacaville Wrestling Scholarship, c/o Mike Martin, 512 Marbella Lane, Vacaville, 95688.