I'm not sure if you realize it or not, but the last item you showed a picture of does not have any electrical components to it. It looks to be to be a purely mechanical lever that activates buttons on a camaro that are already present.
I've looked into this quite a bit myself, but more on the side of adding SelectShift to my non-SelectShift vehicle. For me, I need to reprogram the TCM and possibly other modules. For vehicles that already have SelectShift, it really shouldn't be hard to extend wires from those buttons to wherever you want. The biggest issue is finding or fabricating paddle shift levers that look good. Sorry, I don't have any pictures of what I'm talking about.
2012 Ford Focus
Sonic Blue SE 5Dr
203A Package, 6 Speed Auto
Mods: Debadged, 30% LLumar CTX Tint, MS3 RMM, Steeda RSB