We just pulled similar size wires through about 115' of underground conduit. I was shocked at how difficult it was to pull the wire.

Run the conduit in a way that minimizes the number of bends. Have one or two people pushing the wire in at one end while someone pulls from the other. I used a boom mounted on my tractor's 3-point hitch to pull the last 10 feet or so of wire. That's how hard it was to get that heavy wire to go through the bends I had in my conduit. Man, was I relieved to see that wire finally poke through the end of the conduit.