Mike,
Thank you very much for your answer. I am sure John Cofferty is playing in the same time he is singing and I think his voice is recorded on the same channel with a big part of music so I can not do to much vocal remove with this album. 
I am trying hard to understand everything you told me but I am not a musician as you are but I'm learning.Vagone is an excellent program. I already remove vocal from a couple of other songs and I am very pleased.
Thank you again for your help.
Stela