Re: How to wire LED lights
It depends what the wall plug were talking about actually does. If its just a power supply that outputs 12vdc, share you can cut it off and just wire it like a 12v light.
You said they are 5 color LEDs. If the wall plug is also a integrated controller, it could still possibly be done, but would require some dismantling, and minor electrical work. No offense, but its one of those projects if you have to ask, its probaly not one you want to tackle. It would require getting us voltage readings of the circuits and LOTS of pictures.
In this case I think your on the right path ordering them online. If you still want multi color, there are a abundance of color changing 12v kits out there.
Good luck, and post pictures after your done. We love to see light pictures.
Bill