Paris Hilton, Nicole Richie Film 'The Simple Life' Reboot at Sonic Drive-In

Paris Hilton and Nicole Richie are back at it ... ditching their glam socialite life to hustle through the daily grind while filming "The Simple Life" reboot.

The 2000s brats were rocking full Sonic Drive-In gear with name badges in Duarte, California --  they jazzed up their uniforms with their own swag.

PH was strutting in sparkling silver heels and a blinged-out handbag with her name on it, while Nicole rocked some slingback heels and looked equally glam. Both were clearly hiding tight minidresses under those blue aprons.

The duo, known as Silly and Billy on the OG show, are still as funny as ever two decades later ... Nicole even slid into a hot dog suit for laughs.

TMZ broke the story in May ... Paris and Nicole were all about the reboot, but sources told us not to expect a carbon copy of the OG, which ran for five wild seasons from 2003-2007.