1” is pretty heft, however it is doable...as edge indicated, you will need to allow more time and fuel to get the thing stabilized, but once it is stabilized, and with proper fire management, it should capable of taking on a slug of cold meat, hold a fairly tight range and have a quick recovery when the cc door is opened.
Given you have the equipment on hand (don’t forget that should include welders and torches) the to handle the build, there is no reason to be afraid of giving it a try. As you indicated, heavy plate and extra heavy hinges for the door are in order for a firebox that beefy.
Good luck, don’t for get to post pics of the build.