I think tha was me, Marq. It wasn't too hard to add metallic to the process, just an extra step.
I used a silver metallic rattle can between the coats and sprayed very lightly from about 2 ft away. Not enough to apply color, but enough to stick the metallic in place.
One color coat. light rattle can for metallic, second color coat, wetsand. Lather, rinse and repeat
Didn't turn out perfect, rattle cans tend to spit the occasional glob. It worked out well enough for me, though.
This pic is after Moparfest this year with the retirement home on the back.