Turbo Manifold warpage

Hi I'm new to the turbo manifold world and was wondering what would be the best way to minimize warpage from heat when welding up the manifold and flanges? Mocking up a turbo kit right now and I've notice that could be an issue later on. I tried to have a zero gap tolerance fit up and a consistent bevels and I also weld my manifold outside of the jig to prevent jig warpage. Any kind of feed back would be much appreciated 🙏

There's a chap asking this sort of thing on the fabrication forum, if you check there.