I've been kind of working on this in the background but I can't seem to make it happen. Maybe somebody on here knows someone that can get this done.
There's two ways it can happen:
1. Modify camshaft on head without a DI pump (no you can't just use the existing cam from the other head) and modify it or copy it and put DI lobes on it. Make a new valve cover to mount it and new hard lines. Split the incoming low pressure feed lines (you'll need to do an in tank fuel pump upgrade as well). I believe that you could split the wires between the two spill valves and work. Of course testing to prove my theory would need to be done.
2. Create a reservoir/DI pump mount with basically just the lobes from the cam, picture a power steering pump assembly - you'll need to make a mount to affix it to the block of the engine and figure out a pulley system to drive it off the belts. You would mount second DI pump to this resevoir (to hold oil to lubricate the lobes and pump). New hard lines, split incoming lines etc, same as #1.
#2 is much easier to create and make happen, it would definitely fit/mount on the truck and making pulleys etc would work. I would suggest a 1:1 ratio so that the cam spins the same rpm as the stock cam. (When I say cam I mean a rod 2" long with the same DI pump lobes as the stock pump mounted inside of a reservoir that holds oil and the top is a mount for the DI pump.
Will this cause issues with belt slippage etc? No idea but I think it could work, who knows if it will.
Somebody take my idea and run with it, if you can make it and you want to be nice give me a royalty for my idea, if not then take it and just help make more fuel for the truck and cars.
With this idea I believe we could make enough fuel for 1K+ HP on gas and 800 or so on E85 with stock DI pumps, when the new Bosch pumps come out add 50% supposedly.