the hayden fans out of the box are set up as a pusher fan. it'll say black is positive on the fan lable, as well as in the instructions. what you need to do is remove the fans, flip it over so you can see the fan blade, the silver nut, remove that and the little washer, pull the fan blade off and flip it, the motor has a flat spot on it so u gotta line up the hole on the blade. reinstall the washer and nut. reinstall the fans and wire it up with the black wire to ground. now it is a puller fan.
you should wire the fans to the stock wiring. if you don't want to cut the chassis wiring harness you can remove the connectors from the stock fans. the A/C fan has a pigtail for its connector so you can just cut that and splice it. the radiator fan needs to have the motor opened up so you can cut the connector off it and solder wires to the pins, obviously after this the radiator fan will be garbage.