Onan 4000 Intake Manifold replacement

Hello all, I am the second owner of a 2010 Forest River SandStorm 210SLC with a Onan RV QG 4000 EVAP Spec: K. The previous owner had a lot of carb issues and would replace the carb every year or so. During one of his routine carb changes, it looks like he busted the end of a bolt in the intake manifold leaving only one bolt holding it together. I'm looking to replace the intake manifold but can't find much info on how it comes out. Its very tight and was able to loosen it but its pretty locked in with another parts of the generator. (I'm looking to replace as part of the threads are stripped as well due to his effort to fix)

Has anyone had the pleasure of replacing their intake manifold on their Onan 4000?

Thanks,
Brett