In their book, "Convert It", Mike Brown and Shari Prange say the process of feeding heavy cable through conduit is like feeding an uncooperative python. After having done it myself, I think it is more like feeding a live python to a live anaconda... but I managed to get it done.
First, I had to remove the conduit from the Jeep. If the conduit is not fairly straight, the cable will hang up on the twists and turns and not feed through. So, I took it down to my laundry room where it is nice and warm, and proceeded with the feeding.
The long cable has both the 4/0 cable as well as a 10-gauge cable (for the most negative attachment to the charger). So, I taped them together at roughly 12-inch intervals. I then fed a plumber's friend through the conduit, and taped the cables to the wire:
With liberal applications of electrician's slime, and alternating pushes and pulls, I managed to get the cable through the conduit:
The shorter cable (from the rear seat racks to the front rack) went more easily - it is just the cable, and a shorter run, so I was able to push it right through (again, with a liberal application of slime). I finished the ends (one end a CamLok connector, the other end a standard lug):
I also finished the ends of the longer cable - lugs on both ends:
And then I replaced the conduit on the Jeep, but now, with cables!