I designed 20 of the Richard Stark (Parker) novels for the University of Chicago Press and they asked me to design the Grofield ones as well - The Dame, The Damsel, Blackbird and Lemons Never Lie. The 4 Alan Grofield novels work in tandem with the Parker novels.They wanted a visual connection to the first series but also wanted them to stand on their own.
Instead of a gun silhouette as the identifying motif I went for a silhouette of a "dame" - intentionally cheesy - to highlight the fact that these novels are kind of pulp-y and are a little more about women and relationships. I inverted the visual content from the first series and put the illustrative elements inside the silhouette. The first option below was a deemed a little too cool and sci-fi looking.
I went back to the gun motif but updated the style of revolver because these novels take place in the late sixties and early seventies. They wanted Richard Stark to stand out more as well. I thought it would be cool to treat his name as though it were a cheap motel sign from that era. The idea would be to have a different sign for each of the four novels. I also injected more colour as befitting the time period.
This option had to be reined in a bit because we were moving too far away from the Parker series and there had to be a stronger connection. Richard Stark's name, a huge selling point, had to be more standardized and quickly recognizable. I went back to the woman silhouette and used the motel sign idea for Richard Stark but treated it the same on all of them.