lockone
+1y
All of the stuff you have named will work fine. The only thing I see is that the RE8s might be a little large for the front. I usually use Conitech 2800 4-ply, Airlift 2B7s, or Firestone 2600s. The RE8s might work but it will be alot to cut out of the spring pockets.
On the rear if you run a 4-link you dont need the panhard bar unless you just want it on there. If you are just going to lay frame an 8" notch will work fine w/ 22s. You will just have the normal cutout in the bed which you can make a round cover for and still do everything you would with a normal bed. The rear bags depend on what you are wanting to do and alot of people have there opinions to what bag to run in the rear. Most of the trucks we do that still haul trailers have Contitech 4plys(or an equivalent) or the F2107s.
As for the dually fenders it depends on what wheels you use to what mods you are going to have to do. With the standard semis you will have to widen the fenders and stretch them upwards, or you could narrow the rearend or swap to a shorter rearend. I sale a wheel that we have dubbed the "TOWNASTY" that allows you to run your stock rearend and only stretch the dually fenders upwards.
I think that that is about all if I have missed anything or left something out I am sure someone else will cover it.
Good luck and have fun.