belly pan on the Dodge diesel
 

I panned about 85% of my truck so far.
The frame of the truck is not straight. It bends up near the forward leaf spring mounts.
http://i810.photobucket.com/albums/z...oroblast15.jpg
To keep a frame jack point accessible, I made a jacking extension with 4" channel and 2" heavy angle. It is bolted to both the frame flange and the face of the frame, using existing and new bolt holes. After I fabbed those, I installed them and then jacked the truck on the new extensions.
http://i810.photobucket.com/albums/z...oroblast14.jpg
For the framework, I used some galvanized channel from a surplus metals yard. Each 10' length weighs 2.8 pounds and I picked up 10 for $14.
I utilized 1/4" threaded rod and nuts, drilled and tapped the frame to stand off the channels.
This made the whole grid work adjustable. When I had it the way I wanted, I trimmed off the excess rod.
http://i810.photobucket.com/albums/z...loroblast5.jpg

Some of the channel and rod "foundation".

http://i810.photobucket.com/albums/z...oroblast13.jpg

Looking forward, you can see the crossmember is the lowest point.

http://i810.photobucket.com/albums/z...oroblast12.jpg

Where I could not get a good parallel surface, I welded on tabs to drill through.
Here is the detail around the left A-frame. I can adjust the front framework lower if needed.
http://i810.photobucket.com/albums/z...oroblast11.jpg

Same area, farther back and outboard. Note that I triangulated the channel to give it some stiffness.

http://i810.photobucket.com/albums/z...loroblast8.jpg

front area is about done.
http://i810.photobucket.com/albums/z...loroblast7.jpg

coroplast is attached with self drilling #10 screws and 3/16" fender washers. It was installed back to front, with simple lap joints.
It is below the front frame, so a pocket is needed for hoisting up there. I could go back and make a frame extension in this area if I desire.
http://i810.photobucket.com/albums/z...oroblast27.jpg

cut a window out below the muffler. It was the closest part to the pan, so I will let some of the engine cooling air out there.
http://i810.photobucket.com/albums/z...oroblast29.jpg

same area looking forward. I did not go below the tank and went around it. I did not want to get the pan lower in the back under any circumstance, I wanted it to relieve pressure as it went aft. Going under the tank looked to be too much.
http://i810.photobucket.com/albums/z...oroblast30.jpg

folded detail of front corner. This area will be behind a new bumper/spoiler but I had to finish it off and keep the truck going till then.
http://i810.photobucket.com/albums/z...oroblast25.jpg
Today I brainstormed on that last 3 feet. I can go below the spare and close it in completely. I'll cut a door in the belly to get the spare out if needed. This got the angle to near 4 degrees.
I cannot maintain that to the outside edges due to the design of the boxes, so it will be tapered to the left and right.
http://i810.photobucket.com/albums/z...oroblast24.jpg

you can see the taper in the framework here.

http://i810.photobucket.com/albums/z...oroblast23.jpg

What the shop floor looked like after last night's flurry of trimming. I call it a "coroblast".
http://i810.photobucket.com/albums/z...oroblast22.jpg

I'm one sheet short :(
The back will go unskinned till I get back on the hoist and have the materials.

Wow! Looks great and that back bumper is pretty special too. From your last photo I wonder if you will have a deflector to keep the section behind the axle from scooping up air. My belly pan v1.0 hit a gust of wind and was laying in the road behind me. I learned to make sure the leading edges are very secure. The trailing edges are less of a concern.

Sweet work!

Thanks guys :)
I stopped on the way today and took a few "money shots" :D
I do have that leading edge of the diffuser too low; I could not see it till I got it down on the suspension. I will raise it 0.5" and it will fold up behind the rear axle for 6" or so to insure it will not catch air.
I took some angle measurements and the diffuser was at 4.5 degrees. raising the leading edge 0.5" will get it right at 4.
I am on a 350 mile road trip today. It feels better in the wind, and seems to coast better/farther. I have no cooling fan, 75% of my radiator and grill openings blocked and the temps are good. I was just bumping into 190 F or so climbing a 4500' pass @ 45 F Outside Air Temp (OAT), Trans got to a high of 171 F. On the flats it is running 187 F and 152 F @ 60 F OAT. I have a 190 F thermostat in there.
Temps run up with the EGT. Cruising EGT is high 300-low 400's on the flats @ 60 MPH.

One really sour note: one of the supposedly "checked out" injectors is leaking at the body. I will be demanding a full refund :(

$$$$$$$$$
 

Looks like a money tree! Nice fabrication.Especially the adjustability of the superstructure.No doubt it will copied.Diesel refineries probably won't like it at all.;)

Nice work.
And that bumper. Wow ! I thought mine was big.

Well, I "want" this to work for the OP . . . but if it does it hardly leaves me with any excuses not to the do the same (the same way). Ahh, I've got it: I don't have a lift. [Etc.]

I really expect that the clean-up of the rear will be noticeable. Past midpoint on these trucks starts to really get "dirty".

Looks great, and I look forward to more!

.

Did a bunch of driving today in high 80's temps. The belly pan has taken a set in a few places :)
Posted a new high MPG for towing, and was able to drive 60 MPH and not need the cooling fans except when merging for about 20 seconds, and twice to cool down at a rest area before shutting down. Ambient temps were 60 to 80 when towing.

Dodge
 

Since pickups are some of the worst offenders,belly wise,with deep ladder-type body on frame construction,you're looking to knock off 0.07 from your Cd according to Carr's research.And it doesn't
'show.Nice!:)

so now I'm down to .60 eh?
:eek: :p