Four former Serra Nissan employees charged in connection with a conspiracy at the Birmingham car dealership to fraudulently boost loan approvals and car sales pleaded guilty last Wednesday in federal court, announced U.S. Attorney Joyce White Vance, IRS Criminal Investigation Special Agent in Charge Veronica Hyman-Pillot and FBI Special Agent in Charge Roger C. Stanton. D. Scott Burton, 36, of Odenville; Michael J. Wilkinson, 56, of Moody; Terry W. Henderson, 39, of Pleasant Grove; and Roland W. Riley, 28, of Birmingham; entered their pleas before U.S. District Judge Virginia Emerson Hopkins.