Progress update ..
For anyone doing this in the future, the parts needed are:
Gaskets for the header to engine: 996-111-107-55-M17 ( $5 each from pelican * 2 per car = $10 )
13MM bolts to connect the header to the engine: 900-378-131-00-OEM ( $3.25 each from pelican * 12 per car = $39 )
Gasket that connects the mid pipe to the header: 996-113-113-00-M30 ( $5 each from pelican * 2 per car = $10 )
While I wait for those to get here I wanted to get all the stock stuff unbolted first. Started on the headers and got 11 out of the 12 bolts off. Stuck on the farthest bplt toward the front on the passenger side header. Can't seem to get sockets in there without removing some other pipes, and cant seem to get enough torque to undo it with just wrenches. Any tips for that ?