I think the artist who's most remembered for his relationship with Thin Lizzy is Jim Fitzpatrick. In the following series of images you can see the comic influence in his work. I can see some nods to Jack Kirby, or maybe early Barry Smith? Also, some Phillipe Druillet?
Back in the day, a mate of mine had the Chinatown dragon painted on the back of his leather jacket, which looked pretty cool. He did it with Airfix model paints. Being enamel, the paint cracked over time but it gave the image an antiqued look which worked too.
The final image: an unused album cover. You can't get more comic-y than that can you?