Is there enough meat on your air gap to mill out the secondaries, so an adapter isn't needed. Does the air gap accept the tq bolt pattern? Just a thought
No there's not enough 'meat' there, they are not like the LD340. It might be worth getting the top of the manifold welded to create enough room to do the job, with the added bonus of not having to use the 1" adaptor, and another bonus of the adaptor not being a restriction either.
