exhaust manifold stud 100%. speaking from experience as i had two broken studs that got extracted this last weekend. doesn't look like it's broken off too deep, but you do have to pull the manifold to fix it. honestly, go aftermarket on the rear motor mount and get it lined up well and proper before bolting the downpipe to turbo and downpipe to midpipe. i have to mess with my RMM or my downpipe as it doesn't line up one bit, and i'm at risk of breaking more studs myself