@BrightAyes
As mentioned the OP was looking to find base tune on the lowers, and the North and Quantum tuning guides are a little vague on how to achieve base tune on the lowers. Ullman's guide is pretty good at explaining how to find base tune, even on lowers. All three brands base tune...
A good way to find base tune for lowers is the Ullman method.
Ullman wants you to tune your uppers to base tension on the Loos gauge, then turn the lower shrouds to #18 on a Loos B tension gauge evenly, then loosen 15 turns (half turns if using open turnbuckles) for correct lower sag at base...