1968 was the year Richard Sias's redesign of the Charger went to production — the recessed grille with the rotating headlamp doors, the Coke-bottle profile, the flying-buttress rear quarters, the recessed fastback rear window. The base car (XP29) carried all of the same body work as the R/T (XS29); the difference was equipment and the engine option list.
Base engines: 318 2-bbl (G), 383 2-bbl (H), 383 4-bbl (L), 383 4-bbl Magnum (N). The 440 Magnum (P) and 426 Hemi (R) were R/T-only on the 1968 Charger. Built at Lynch Road and Hamtramck.
The 1968 base Charger is the cleanest example of Sias's design intent — no aero homologation addenda, no R/T striping, just the body. Plenum decodes it via the 1968 B-body broadcast schema; the XP / XS body distinction in the VIN tells you which trim shell you're reading.