Help with wiring diagram

[NSANE]

I have a mx-3 and want to put the 3 position switch in. I have the article and diagram from the post on dooing it but just need some help understanding the diagram. From what i can tell you remove the 2 pos switch, solider in a wire to the center post (signal) and solider wires to ground and 5 volt power. Then the 5volt goes to one side of the new switch the ground to the other but I am unclear about the center wire with the resistor as to how the resistor gets solidered in and how it works. Do you just t the resistor in to the center line anywhere and the other end of the resistor gets a wire going to ground? Can it be the same ground that the other switch wire comes from. I dont understand how this creats 2.5 volts going to the signal wite when the switch is open. Any help understanding this would be great i did a tq3 mod so as long as i have good instructions i can figure it out but the resistor is throwing me for a loop. Thanks in advance for the help. RCCrawler.com- Your #1 source for Radio Controlled Rockcrawling! this is the page i have been using.

[NSANE]

Found a link to a sight in spanish. but it works!