Gen III Hemi Swap Questions

So as I'm finishing up my truck, I'm starting to do research for my next project, my 1968 Barracuda. It was a 318 auto car, nothing special and the original drivetrain is long gone, so I decided to Swap in a new 5.7 Hemi.

Now I have some criteria for the build and would like to see if anyone has done it yet or it is even possible.

For the suspension I want to keep torsion bars, I have a spool mount K-member. From what I read so far I have to notch the K-member for some clearance, and use a Milodon oil pan. Manual steering is no problem.

Engine looks like a truck Hemi is the easiest one to use because of how the accessories on the front are mounted (correct me if I'm wrong). I want to retain the fuel injection system. The Eagle Hemi are better? I would like to be in the 475-500 crank horsepower area.

Now for the transmission. The car was originally equipped with a floor shift automatic, I would like to keep that, but I want an overdrive transmission also. I know that I would need to redo the trans tunnel and torsion bar crossmember. Has anyone done a 545RFE swap and kept the floor shift setup? Or I could go to a 46RH, then i wouldn't have to worry about as much wiring, but can I get the floor shift setup to work with that trans also.

So factory or aftermarket PCM for fuel injection/ transmission?

O and one more thing if its not to much to ask. I hate drive by wire throttles. I would like to switch to a throttle body that actually is connected to your gas pedal like its supposed to be. I think I read somewhere that Mopar Performance has that throttle body?

I'm sure I'll have more questions, that's all I can think of before I head off to work.