Alternator wiring

I know this subject has been brought up before several times. I've used the search feature and found all the different wiring diagrams to wire up the square back alternator for the early type charging systems. My question is: I know I have to run a wire from the second field post on the alternator to the voltage regulator, do I really need to splice into the wiring on the voltage regulator or can I just use a splitter on it and attach it that way. The voltage regulator I am using looks like the original black box, except mine has the circuit board internals. Thanks in advance.

Dan in Silicon Valley