I agree with twozs about a mistake that left off the rain gutters. Cars were built according to the build sheet and inspected to make sure the car matched the sheet. Mistakes were not common. Probably more likely would be a situation that we don't know the exact details about what options went with what parts. My 70 does not have RS or Z21 trim, so it didn't get the rain gutters. That makes sense. But, the dual ring tail lamps that Chuck Sharin has pictures of above were also an RS and/or Z21 trim part. If everything followed what we know about these cars, my car could not have the dual ring tail lamps. Yet, it did come off the assembly line with the dual ring taillights. To add to the confusion, my build sheet specifically calls for the T93 Special Tail Lamps and they are on the car. So, the question is, why? They shouldn't be there if you needed RS or Z21 to get them. The rain gutters could be the same thing.