He appeared on their recording of Al Kooper's song,"Brand New Day." Weeks also played with the Fabulous Amazers and Bill Lordan (pre Robin Trower drummer) in the Minnesota group, Gypsy. He also played bass guitar for Michael's Mystics back in the 60's in Minnesota. Bill Lordan was the drummer of that band as well. That band recorded "Pain" by the Grassroots, a big hit locally for the Mystics. In addition to his red 1962 Fender Precision bass Weeks also uses a maple-neck 1958 Precision, and a 1964 Fender Jazz Bass, as well as a tobacco sunburst Kay four-string acoustic bass for Clapton's "unplugged repertoire". Weeks used a sunburst 1963 P-Bass during Clapton's 2008 European Summer tour. In 2014 he began using his "WW" Willie Weeks signature bass by Bee Basses. On the 2009 Australasian and British tours, Weeks played Fender, Kay and Alleva Coppolo basses. Weeks appeared in the films "Blues Brothers 2000" (in a fictional supergroup along with other musicians he's worked with) and "Lightning in a Bottle". With Rod Stewart With David Bowie With Bette Midler With LeAnn Rimes With Gypsy With Etta James With Joan Baez With Rodney Crowell With Tanya Tucker With Jimmy Buffett With Boz Scaggs With George Harrison With Rosanne Cash With Chaka Khan With Ronnie Wood With Gloria Gaynor With Kenny Rogers With Peter Cetera With Steve Winwood With James Taylor With Stephen Bishop With Gloria Jones With Vince Gill With Michael McDonald With Leon Russell With Wynonna Judd With Donny Hathaway With Eric Clapton With Maria Muldaur With Amy Grant With John Mellencamp With J. J. Cale and Eric Clapton With Herbie Mann With Randy Newman With Joe Walsh With Aretha Franklin With Rickie Lee Jones With Carly Simon