I need to rewire a phone jack back to a different number. How do I do this? Any help appreciated.

I need to rewire a phone jack back to a different number. How do I do this?? Any help appreciated.how many number do you have in you main box... normally the tele comp. just switch the wires in their OWN BOX... ussually there are only two wires to exchance... if the wires for the new number are coming directly from the house main box to the jack you want to change then you only have to switch 2 wires... if not you will have to trace out every jack ( tap) in between and switch the wires

Normally the first line uses the red and green and the second one uses the black and yellow, so you just have to switch them. Unfortunately I am not sure which is which. Some time ago somebody explained very well even giving names to the red and green wires. If you dig deeply enough, you might find it.

Thank you so much for your help I will open it up and see what I can do. :) :)