Maybe it was a local thing, but back in the early '70s around NYC, if your car was set-up "right" (?) you had: the traditional "HI-Jacker" air shocks, gold anodized Moroso valve covers (with wing-nut bolts), Thrush, Cherry Bomb or " Purple Hornies" glasspacks, small lights in the wheelwells (why, I have no idea), L60-15 tires out back, 950cfm Holley, Tarantula manifold, Accel ignition, pinstriping by a guy named Vic Kessler and at least 1 "Connecting Highway Street Race Winner" decal in the 1/4 window.
Of course if you were a SERIOUS NYC streetracer the car was as much of a "sleeper" as you could possibly make it, you NEVER opened your hood & your races were always set-up for the early morning hours, usually at some obscure road.