CHATTANOOGA, Tenn.---Chattanooga head wrestling coach Mark Leen has resigned his position effective immediately, UTC athletics director Oval Jaynes announced Wednesday.    Leen served as UTC's head coach for six years and compiled a 43-35-1 record. He led the Mocs to three consecutive Southern Conference wrestling championships in 1998, 1999 and 2000.    Jaynes said that assistant coach Franky James has been appointed interim coach and will handle the team until a permanent coach is named.    James is a 1998 graduate of Carson-Newman where he was an NCAA All-America wrestler at 149 pounds. He also wrestled at the University of Oklahoma before transferring to Carson-Newman.