Solid floods of color can be tricky with letterpress. But if you play your no-pun-intended cards right, you can get great results. Lighter/brighter colors tend to print more evenly. And die-cutting the cards rather than knife trimming can help keep the raised unprinted paper from getting squished or scuffed.
For these square cards we printed for Birmingham Developer, Ford Waters, we printed on separate sheets of 300g Fluorescent White Lettra, then duplexed and die cut. Design was done by long-time Parklife friend, Chad Martin of The G Brand.