Although not a L48, at least another possible '69 data point.
The attached picture shows the PCV hose /tube connection from my '69 LF7 (327 / 210 hp) engine. Although this engine is not original to my car, it is a '69 327 Camaro engine that I personally pulled from VIN #124379N551248; engine code V1122FJ; (Flint engine, 22 Nov 1968 engine assembly date, 3 sp manual tranny) back in March 1994 when that car was being parted out.
The metal breather tube and rubber hose connecting the metal tube to the air clearner were on the engine when I pulled it. The rubber hose has yellow GM markings on it which if you look very closely at the attached pic you can barely make them out.
Don't know if these pieces were original to the engine at the time of assembly in 1968 or not, but they were there when I pulled it in 1994. They are on my car today.