So tried fixing a bad leak where the header and motor meet up.l with new Subaru gaskets. Fixed 1 side but the other is still leaking. Any ideas. Is it common for this mounting area to warp either at manifold or headers. Just looking for inputs before I yank everything off again to see if the header is level

 

Not too sure about common but it happens, usually the heads rather than the cast iron exhaust manifold. You can plane the header flange down possibly after running a straight line across it(ruler, etc).

If you can't get it to seal all the way there's Remflex among other companies that make crush/fat gaskets that are bigger than the OEM ones. Might be able to seal up the space in between hopefully. Hopefully it's not the head surface...

Subaru - Remflex Exhaust Header / Manifold Gasket - Gaskets

good luck.