General Motors Co. says 6,024 U.S. hourly employees have accepted buyout agreements, more than half of the total coming from the auto maker’s assembly plants.

Most of those workers departed as of Aug. 1, GM says, bringing the total number of hourly employees who have left the company under a special attrition program to about 66,000 since 2006.

GM says skilled-trades employees make up 40% of the latest group, and 35% are leaving the company after accepting buyouts.

Of the total, 3,351 workers are vacating jobs at assembly plants, with the Wilmington, DE, facility (Pontiac Solstice/Saturn Sky) accounting for the biggest share at 482. That is followed closely by Orion Township, MI, (451) and Spring Hill, TN, (450). Spring Hill recently lost out to Orion in a bid for a new small-car production program due in 2011.

Another 1,205 workers are leaving jobs at stamping plants, including 574 from the Mansfield, OH, operation earmarked for closing.

Powertrain operations account for 1,066 of the voluntary separations, including 357 at the Willow Run, MI, complex.