1) Remove the base plate of the telephone (using the 4 screws in the corners)
2) Remove all existing wire straps
3) Insert strap between T1 and T2
4) Insert strap between T8 and T9 (as seen on the diagram below)
5) Connect the white wire of the line cord to terminal T1
6) Connect the red wire of the line cord to terminal T9
7) Connect the blue (bell) wire of the line cord to terminal T11
8) Connect the spare green wire of the line cord to terminal T3
9) Insert a 3K resistor between terminals T11 and T12.
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Hopefully the diagram should make this conversion a little easier :-)
Good luck