Quote Originally Posted by McCreed View Post
If the colour shift paint is any kind of lacquer (which I suspect it would be) you can't put a single-pack (hardware store stuff) polyurethane over it. The two are not compatible. Clear coat will need to be lacquer also.
A water borne poly would be compatible.

With the colour shift paints the shift usually comes from a pearl, so if the sparkle appears to be gone then you probably had flakes in there that had settled on the surface. With a base coat/clear coat system, you will find a big difference in how it looks once cleared. You may find the sparkle comes back.