[SuperCars]

The COPO 9737 Exception Control Letter sheet "ECL" lists all the RPO's that are combined to mke COPO 9737. Most of you know it already, but these are separate documents from the Engineering Recommendation Changes or "ECR's". The pre-April 68 COPO 9737 "ECL" does not include the V78 Export on it. But it does include the U18 Speedo/Export. Could it be that Federal regulations only allowed the standard 120 MPH speedo; and in order to have the 140MPH speedo it was only able to be permitted by labeling the car for export. It's likely that pre-April 68 Yenkos having Export Trim Tags may only be from the change to the 140 MPH Speedo and had no relevance to engine changes.

Then when V78 Less Certificate of compliance is listed for the first time on the COPO 9737/Yenko "ECL" of April 68; it most likely was a result of this GM engineers words on the April 68 9737 "ECR" pertaining to Yenko; "make RPO V78 mandatory with Engine Changes". Since the V78 Export prompted by "Engine Changes" came into effect in April 68; the cars "without engine changes" prior to April may've had the Export trim tags only because of the U18 Speedo/Export designation.