Third paintjob from first set (Access), along with first paintjob from third set (Princess Robot Bubblegum) have gradients in them. The pre-done paintjobs of them are opaque, and here's why:
Gradients from opacity to transparency have one issue, due to in-game limitations. In day, the gradients are cropped, due to the opacity in the gradient parts closer to zero opacity is being less than ~104, which prevents them appearing in day (probably it may be used for making license plate lights).