[aerohead]

I remembered to bring the camera and hope Al will be able to post images before the store closes at 4:00 PM.
I'll go ahead and briefly explain the latest mods to the T-100 which went on the last trip:
(1) The nose was re-configured more like the half-zeppelin profile of the 'Template',kicking the air over and around rather than allowing to flow underneath.
(2) Both front wheel arches received for the first time,a rear radius which integrates into rocker panel fairings.Short of full skirts,this is an attempt to clean up the flow here a bit.
(3) As mentioned above,the truck received rocker panel fairings to integrate flow coming from the new wheel arch radii.
(4) The hood blister finally got the plex wing fairing for the driver' side.The T-100 has a fairly mediocre windshield and the blister with wings attempts to 'soften' the pressure gradients present before,around,and over the windshield.The proper solution would be a $3,000 GTP compound-curve laminated safety glass windshield and re-engineering of the cabin,both outside the scope of the project.
(5) Driver-side cab/Poco-Loco integration fairing.Finally,after 5-years waiting,I finally have a fairing to eliminate the locked-vortex which occupied this area adjacent to the back of the cab and forward section of the aero-shell "Poco-loco" named from the sailboat from which it is derived.
(6) Passenger side Poco-Loco side window.No aerodynamic benefit but a great safety addition while backing out of parallel parking spaces into traffic.
(7) Rear windshield for Poco-Loco.Again,no aero benefit however I get rear vision for the lane I'm in and vision while backing.The dimensions of the fenestration are the bare minimum for vision,while minimizing the volume of the locked-vortex created by the new void.
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OBSERVATIONS:
Without the 24-inch boattail, missing 2-sections of the bellypan,and missing the diffuser section entirely,over the recent 4,100-mile trip the truck performed close to the 2005 performance which included the tail,full belly and 1st-gen trashcan nose.
At a trip average of 31.3 mpg and mileage ranging from 28-36 mpg it appears that the new mods are allowing 'long' truck mpg from the 'short' truck.
It should only get better from here.
On a velocity-weighted basis,using the MPG data through the 'back door' of GM Lab's Cd/MPG relationship,the truck's mpg would indicate approximately Cd 0.20 compared with the original Cd 0.44.
If things fall together over this next year we may finally know if the trailer can push the Cd even lower.