On the Trans I ran 2 foot of Stainless Braided PTFE -6 an out to the frame rail. From there it goes to 3/8 steel lines all the way to the cooler which is in front of the radiator. I used 2 foot of PTFE hose because it is flexible and can easily be moved out of the way if the trans ever needs to come back out.
Fuel Feed is Dual -10an or 5/8 from the sump with dual 10an filters before the pumps.
-8 an or 1/2" after the fuel log into both pumps.
-8 an or 1/2" after the pumps to Y to single -8 an or 1/2" to regulator.
Single -8 or 1/2" an return.