Don't know about the rest, but the most expensive Mercedes WAS the 600. My Nitske books says

in October 1969 (1970 model)

Limousine $23,580
Pullman $26,953

October 1970 (1971 model)

Limo (east coast) $25,707 (west coast) $25,920
Pullman (east coast) 29,385 (west coast) $29,617

Looks like prices jumped up in '71

limo (east coast) $32,695
Pullman (east coast) $37,928

Kuan

KUan