Paul,
I am glad you got that one and have the resources to go all out on restoring. It will, I am sure, be a stunning beauty! The firebox design is the same as my 1st generation Summit. I am sure you will disassemble the aluminum end pieces from the front and back center sections made of porcelain coated steel.
Media blasting the end pieces will be the classy way to go, while the center parts are like cleaning a Genesis hood to bring back the porcelain shine. I replaced the old bolts with stainless. If it is like my Summit, there will be RTV helping to make a secure contact between the end pieces and the porcelain centers. You will have to get all that off and get a new tube to put it back together.
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Finally, you can see that just like
@LMichaels noted, while the inside of the aluminum side pieces are bare, the top part that shows (and is not inside the cooking area) is painted black.
My picture includes the stainless reinforcement panels I had made applied to the porcelain front and back. Based on the appearance of your new Flat-Top, I doubt you will need to do that.
Not having your budget to redo my Flat-Top, it won’t look like yours, but I am going to do my best this summer to give it a new lease on life. And it will definitely see action! I even have a party hat picked out to wear while grilling on it!
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Last thing. You can get half griddles that fit the current Spirit 300 that will substitute for a single grate. That is how the Flat-Top originally came. However, if you get the Crafted Kitchen insert designed for the Spirit 300, you could use any of the CK accessories including the larger griddle that will cover almost 3/4 of the grill.
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