There are a bunch of threads on here about hardwiring a radar detector, but nothing definitive.

Sounds like I have to wire positive to the sunroof positive and run a ground wire down the a-pillar to a ground in the fuse panel?

What about running both wires to the fuse panel and tapping into some component?

 

You could definitely do that, I would just make sure its a switched source so you can't accidentally leave the radar detector on after you turn your car off.

 

when i bought my s4 the previous owner had hardwired both wires into the sunroof area, worked fine until i pulled it out. i just didnt like the wire running up there