Wiring issue with voltage regulator

Yea seen that as well but nothing I can find explains exactly where the blue wire goes. One diagram I found shows it goes to ignition 1?


This doesn't explain it?

Dual_Field_Alternator_Wiring.jpg

There are two IGN feeds coming into the engine bay. One is the brown bypass circuit IGN2 and it's only hot for starting

The other is IGN1, normally blue AND IS THE ONLY source of switched ignition power coming into the engine bay

The wire from ignition switch going to the top of the ballast is indeed IGN1