Starting restoration on Weber Genesis Silver B

A few days ago I picked up an old Weber Genesis Silver B for $80. I'm taking it completely apart and would like to make it a nice grill for my family. This is the very first grill I've ever owned and I'm excited to use it.

I have a few questions about the restoration process. Here's a link to a few photos of the grill -- https://imgur.com/a/AKwXBv3

Beyond making it looking pretty, do I really need to angle grind the inside of the firebox down to the metal? I was planning on just scraping away the black carbon buildup and that's it. Also as I started to scrape away the carbon from the lid endcaps I noticed it's showing a kind of cruddy white metal underneath. I'm not someone who has done much of any car / grill restoration so I don't know -- is this rusted metal? Is it basically just fine as is (minus scraping the carbon off)?

I'm thinking about painting the outside of the firebox, the outside of the endcaps and also the frame (though the frame seems to be in really good shape with virtually no rust so maybe I will skip painting that part). Would scrubbing with Simple Green and some sand paper before painting be good enough?

Thanks for reading my newbie questions.

No need to wire brush it down unless you want it sparkly clean like Bruce's refurbs. If for your own use I'd just scrape it

Like Larry said my personal grills I just get the big chunks off. Those I refurb to sell I get it all off. It's just going to get dirty with use. Use high heat paint for the fire box and endcaps I just use regular paint for the frame. If painting the frame I wash it with dove dishwasher soap and water that will cut the light grease that may be on it. If there are big gobs of grease a putty knife or razor blade scrapper will work for that.

I would not blame you one bit for wanting to clean that firebox and lid thoroughly, even for personal use. That grill is pretty gross.

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