A young Little Richard is seen performing rock n roll at a dance in 1958. Little Richard had in fact quit rock n roll music the previous year, become a born-again Christian, and would focus on gospel music until 1962.
"Bones" suggests that "Hawk" buy a new Skylark. This episode takes place in 1958. Buick produced Skylarks in 1953-1954, and then not again until 1961.