Later engines were all roller cams . I put rollers in my 496Should be a rollerized gen three engine. I'm bad with C2 C3 stuff also. 68-90 take all the same bearings rods and pistons. Valvetran changes, accessories and injection was pretty new on the Vortec setup through the 90s and it changed three times. I think in 2000 the fuel pump provisions for a mechanical system were phased out of the casting.