this was the cover from december 6, 1954 life mag. according to mouse and grimshaw it was purely coincidental that they both used the same image within a couple of weeks of each other.
seeing as how there was no real coverage of the hippie scene and psychedelic posters in the mainstream media until the January 1967 'human be-in' in golden gate park, it would have been relatively hard for anyone to know about mouses work on the west coast within the time frame that it happened.
life magazine was/is a treasure trove for poster artists, and also inspired grimshaws "seagull" poster, his first poster, which was the grande ballrooms first poster also featuring the mighty MC5, Detroits version of the SONICS.
the prime movers featured another michigan native, front man michael erlewine, known for founding allmusic.com.