i purchased an all pro front hanger with shackles for my 87 sas. i want to make my own hanger that drops the front mounts another 1" down in addition to what the all pro hanger drops them and move the mounts another 1" forward(2.5" total forward, and 2" down). i think the all pro shackles are 5" from eye to eye. how much longer of a shackle do i need to make roughly to accomidate the new front hanger postion?

the shackle will go throught the frame.