Quote History Quoted:
I can tell you for a fact that Holloman AFB will be unloading about 14-600 gallon F-4 centerline tanks, 16 or so 370 gallon F-4 wing tanks and 3 travel pods.
I've heard over the years that the travel pods were converted napalm tanks from Vietnam, I don't know if that is true or not.
View Quote
But those would be the "new style" centerline tanks, which are like F-15 centerline tanks. 3-piece construction, nose cap, straight tube body and tail cap. Very different compared to the old-style oval shaped, 2-piece (front half, back half) tanks that bolted together in the middle.
The 2-piece design would fail at the seam and I saw one F-4 have a tank split in two while taxiing. One big shit show when 600 gallons of JP-4 splooshed onto the ramp. In flight the old tank was only good for 4 Gs when full. The F-15 tank was good for as many Gs as the F-4 could handle.
The AF F-4 world converted to the "High-G Centerline Fuel Tank" aka: the "F-15 tank" in the early 1980s. Externally it was the same tank as the F-15 but internally (plumbing, electrical) they were totally incompatible if you thought about interchanging them.
For building a belly tank roadster I think, the 2-piece tank would be preferable. You could slice the sections along the mid-point and have a 4-piece body that would allow work on the car by only removing the top sections and, with the engine cover section having quick-release fasteners and the other 3 sections being screwed into place.
As far as those travel pods go, yes the first ones were unused napalm canisters. As the supply of parts went away the fabrication shops simply rolled their own. The first ones were napalm canister kits with a door panel cut into one side and a hinged-mounted door panel installed. The post Viet Nam examples were copies built out of sheet metal in under a day.