[gumby79]

If im understanding correctly the 5 sided box that sticks out 3"per side and a brick shaped hitch cross member is the best cleanup I can expect.
Ive heard sence I was a kid that a rollpan bumper with a hidden hitch was about the best aerodynamic package you can do to a pickup. Nowdays its airdams , side skirts, aero caps,and belly pans and many more on top of the tryed and true Rollpan . Iam merely trying to tie it all together and figure out a long term plan.

I have a tendency to dream big. Some times to big.
So for this level of mod some extra steps are needed.
1 full belly pan
2 side skirts
I alluded to side skirts by asking for advice on width "hitch wide or out to side skirts as rear mount" under "Request for Advice #4"in drawing picture.
3 ??? What else keep them coming this is another high-school idea like the cap its purpose and design have adjusted to changing life ... I cannot see all the shortcomings but I can adjust to the ones that are visible to me or others. Eg I saw that the supper aggressive Airfoil could be to much and said it could be flat if nothing mote than a pice of sheet metal pop rivited as a tail cone...

Airfoil could be flat. Purpose for airfoil is to streamline the 4.5"sq ×1/4" hitch cross tube.

Corection the hitch is 38"w 2.75×2.75 sq. It hangs 13"lower than the lowest sheet metal and 17below the bottom of the bed over a foot off the ground.

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---- how about part 2 idea #1
Boat tail patch panel to allow the tailgate to be set at ??°as a rear diffuser . The gate idea would work better minus the the giant hallow ,parachute 5 sided air scoop they called a bumper in the 90's and a rearbelly pan from the rear end. I have a 4 ×8 sheet of plexiglass from an old sign to work with just trying to think of a best use of it but mixing a 4th consept in I felt was too long a title blending 2-3 into one build is complex enough .
I like the suggestions so far it just increased the #of concepts
The center belly pan should be simple slap a flat panel to the bottom of the running bords with dutz aircraft fasteners into the cross stringers . add the missing section between the cab and rear wheels wala a belly to the rearend. Corce have to accommodate the drive shaft . This is what we had to do to our street stock with a custom floor pan also make room fore 2 6"×36" glasspacks. All with in the scope of my toolbox of understanding and skills my shapes are dreived by eye not computer programs so my thinking is a little different but we can communicate (as long as you can figure out the Cypher)sorry bad spelling and composition but I do try.
Gumby Stay Flexible