autometer triple gauge wiring to fuse block question

Hey guys,
This is probably going to be an easy one for you all. Im not too great at wiring so I just want to make sure that Im okay with this. I have an autometer triple gauge that quit working. Ive never had to mess with it as its worked great since Ive owned the car. 69 Dart btw. Following the wiring to look for a short or blown fuse and noticed that the red wire which I believe should be fused before it goes to the +battery was inline with one of the fuses from the block and came loose. Was just hanging there which made it easy to see that was the issue. Problem is I dont know which fuse it was "clipped" to. I tried it in each one and saw that the gauge worked when placed with the top three only when key was on...which is what I want. Im assuming one side of those is a battery feed and the other is for things like flashers, tail lights, cigarette lighter, dome light, etc. But I dont know which is which and if it even matters. I assume I can just clip it in with any one of those 3 and it will be fine as they are only hot when key is on. I put it in slot #5 for now. But I want to make sure by asking you guys.
Sorry for the long winded explanation and if this is a super basic wiring question, but like I said, just want to be sure.
Tried to take a pic, this is about as good as I could get. For clarification, Im referring to the red wire in slot #5. Not the white in slot #1. To be honest, Im not sure where that white goes, I tried to follow it and got lost up in the steering column...
Any help is greatly appreciated.