The 1967 El Camino followed the Chevelle’s styling facelift with a new grille, front bumper, and trim. Air shocks remained standard equipment on the El Camino, allowing the driver to compensate for a load. The 1967 model year also brought the collapsible steering column and options of disc brakes and Turbo Hydramatic 400 3-speed automatic transmission. It was the second year the 396 (L35, L34, and L78) could be had in the El Camino (both 13480 300 Deluxe base and 13680 Malibu series).
Since the L35 396/325 hp engine was the base for the SS396 series, the number of L35 engines reported sold by Chevrolet in 1967 (2,565) were sold in one of the two El Camino series, which were the only other series the engine could be ordered in. Since the L34 (350 hp (261 kW)) & L78 (375 hp (280 kW)) were available in either El Camino series as well as the two SS396 body styles, there is no way of knowing how many of these optional engines went to which body style.
Chevrolet does report 17,176 L34 and 612 L78 engine options were sold in 1967 Chevelles, but there is no breakdown of body styles. The TH400 3-speed automatic was now available as an option (RPO M40) with the 396 engine in both the SS396 series and the 396-equipped El Caminos. The 3-speed manual transmission remained the standard transmission with a heavy duty (RPO M13) also available along with the 2-speed Powerglide and either M20 wide ratio or M21 close ratio 4-speed transmissions. Although there was no actual factory El Camino Super Sport until 1968, many owners have “cloned” ’67 SS396s using 1967 Chevelle SS396 badges and trim.
Source: wikipedia & GM Heritage