How can I access the fan on my Kirby G7E cleaner?

I have a Kirby Ultimate G cleaner, Model G7E & I want to remove the stainless steel/chrome cover. I have taken out all the star screws that I can see (5 front, 1 top & 6 underneath), but I cannot remove the top. I need to get at the fan and insides generally to clean and service them.
Any help gratefully received.