today I port-matched each runner on both sides (upper flange and lower flanges) and grinded away any welding ridge. The flanges are 100% gasket-match so there are no edges disturbing the air flow !
next step is test-fitting the whole assembly with fuel rails, throttle bodies, etc. to check for strut bar options and general fitment.
then I will powder coat the GT-R Adapter and it should be ready for final installation and first engine fire-up
Chris