Chevy sent notice to dealers that as of May 19, 1969 "bright metal" tailpipe extensions would be included with N10, Z27 and Z/28 with those prices increased $15.80. [They did not increase COPO prices]. NC8 chambered exhaust was dropped as an option at the same time. Chambered never had chromed tips; stainless steel was not used.
The few surviving cars with an original revised N10 system show a difference. The RH tailpipe is 2 piece with the lower section chromed. It was welded to the muffler. The LH pipe is the standard production part with the lower section polished and flash-chromed.