I opened the back and it has the same color wires as the four prong I am putting in . Do I just remove all that and put the new four prong in the same way? Thank you

BE Careful! The Red wire is L2, make sure this is connected to the other Red. Black is L1, make sure this goes to the other black wire.
The white and Green wire of the new cord go together and connect to the old White or Green Wire. White is Nuetral, Green is Ground. In a 240V dryer system, Nuetral (white), goes to chassis ground (green).
Rich
Western Appliance Repair of Boise 208-863-3702 (http://www.westernappliancerepairboise.com)

Sorry just saw this. Basically the white red and black will all connect to the same terminals as the 3 prong. The difference is you remove the jumper under the neutral(white) that goes to chasis ground and leave it off. The green wire from the new 4 prong cord will now connect to chasis ground and you will be all set.