You wont have to cut any wires, the harness I linked above just plugs into your stock plugs. then you wire the harness to your new headunit. If your cutting wires your doing it wrong. Also the wires are color coded so just match the wires. Depending on the headunit you may or may not use all the wires coming from the harness this is normal.
ZETEC Crew #26 SR #20 YELLOW BLAZE OWNERS GROUP#4
Moderator Pilot, 12 SE HB ╠╬╝, 2011 Ford Edge SEL AWD