First for your Shampoo attachment, all Kirby generation models came with this carpet shampoo attachment. It really does do a nice job at cleaning carpeting and rugs. In terms of how you use it, here's two links for you, the first is written instructions on how to use it, and the second is a video that shows you how to attach it to your Kirby and use it. In the video it's actually the Kirby Sentria that they use, but the procedure on converting it from a vacuum into a carpet cleaner are the exact same for the Sentria as they are for your G5.
Written Instruction Manual For Kirby Carpet Shampooer
Video Instructions On How To Install & Use Kirby Carpet Shampooer Attachment.
Now in terms of the other part that you were asking about. I believe the part your asking about is called the Intake Guard. I think this is the part that you're asking about, here's a picture of the Intake Guard:
The Intake Guard is connected to the front of the machine only when you want to convert your Kirby from a vacuum cleaner into a blower. This protects anything from going into the fan while it's being run, as well as pushing the safety switch that allows the machine to turn on.
I really hope that this information was helpful to you. If you have any follow up questions, or need further help with your new Kirby G5, please don't hesitate to add a comment here on the Fixya repair page, and I'll be more then happy to answer any and all of your follow up questions.
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