You say "pair 3/4" which means that you are aware that the T&R wires go to the middle pair of pins in the female 6p6c jack.
You are aware, I hope, that even though the pins in the jack are numbered 3 & 4, the pins you want on the station 66 block are 1 & 2.
So, for instance, if you have run 4-pair station wires, and you have terminated the White/Blue pair on the jack's pins 3/4, you would place your cross-connection wires on the White/Blue pairs on the 66 block, which are actually the first and second pins (not the 3rd and 4th pins) for that station cable.
