Yes, either on purpose or by mistake someone used a "heart-donor" early non-HP '68 car.

all '68 GTXs were 440HP (375hp) or HEMI (as were Charger R/Ts & Coronet R/Ts)

in '68 some c-bodies were available with 440 (350hp) or 440HP (375hp)

FYI, all '68 440s were painted turquoise.