Welcome to the club.
Once you get to smoking, most of this will seem pretty insignificant. Tasting the product from these smokers moves us on to learning the process and enjoying the results.
When you look at the inside of the smoker in a couple months, you'll forget weld discoloration--might even seem silly that it was a concern.
Yea. It would be nice if the internal probe hit 210*, but after 190* I don't rely on the temperature. At 190*, I begin to insert a probe into the pork butt to determine resistance. Once the probe slides in with no resistance, I remove the butt from the smoker. It's ready. Many times I don't even know the final temp.
Use this forum as your instruction manual as it's loaded with a lot of good information on the smokers, the process, recipes, techniques, etc. The smoker produces more smoke with usage, and you'll find you will get smoke at lower temps as the smoker seasons. I couple of smokes ago, I saw smoke at 120*.
Smoke something. Funny how the smoker gets better as we gain smoking experience with it.