Bad news...5 miles into the drive...the ducktail broke free from the mounts and drifted off in the rear view mirror.
Guess I'll have find some of that 3M double stick tape that can replace rivets.
MPG estimate is approximately 25mpg. I'll refuel when I git back home in the morning.
The rest of the aero cap is holding up well. No shimmies or shakes. Nothing falling apart.