For the doors I measured the checks with a metal ruler and drew the lines on white primed doors. Then I traced a dime in the center for the circle and painted the black checks, then painted the circle with layers of grey and free handed the heart.
And here is the Storm Raven after some much needed progress. I did the checks on the other wing, the top turret and side sponsons, and layed in some color on the edges. It is unbelievably hard to paint the same exact heart twice free hand. I painted the heart on the other side over a year ago! This one came out a bit bigger, I need to go back and make it smaller. It comes to a little sharper point than the "lamenters" heart. (The one on the razor above is pretty good.)