@ DavidBrennan
I do think there have been graphists who reworked these famous fonts at the time they designed the posters. If you want to make it authentic, just get the higher res scan you can get of the 80's logos. There's no other ways to have them 100% accurate. I never found the least copy or custum logo wich was accurate. And I can tell you people really appreciate these logos when you use the good ones.