Update-
Here are the brackets I found for the center Equa-Flex mount:
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This is where they go:
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Here it is installed, note the paint burnt away, I should put some paint on it. I had to cut the top
opening longer so the bracket would clear the factory weld on the original bracket and fit flush to the frame:
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Here are the outer spring mounts, this was a befor pic and now I am using the bottom hole:
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They supplied a 9/16" pin same as what was originally used and both holes in the bracket are 9/16"
however there was a glitch! [

!]
The upper hole in the bracket was drilled too low so the pin would not go through. If I ran a 9/16" drill
through I would end up with an elongated hole, the available space left was a very tight fit for a 1/2"
bolt so I used 1/2" grade 8 with a jam nut on the inside and lock nut on the outside.
I lowered the pin box 2" and now have 7. 5" bed clearance