I recall I had the same(ish) problem when making the same switch. There is something different in the harness between the idiot lites and guages - some resistance/resistor in the wiring harness. I do not recall specifically and I cant remember what made it all work. It was something fairly easy since I am not all that proficient with this sort of thing.
I mention to reinforce, this may be something usual in making the switch and to move the thread to the top so Bartamos can see it.
