Would seem to me that there was only a true 400 HO. Some sources call it a Ram Air, but GM called it on paper an HO. These option charts were published way in advance for distribution to dealers. Would seem to me that the HO was available only at the beginning of the model year and possibly after printing, the 611/348 codes were available to loosly (but not officially GM) call this new fledgling a RA III. Since all other "Ram Air" cars had open scoops, past and with the RAIV, would only serve as appropriate (whether correct or not) to call the 348/611 a Ram Air, yet, not a "true" Ram Air.
So, I say a 348 coded HO with a 611 optioned Ram Air hood scoop/panned 69 Firebird is a HO. Unless someone can provede a service bulletin or other official document stating otherwise, this to me is an HO. Maybe on paper a "R/A" on the billing history means a 348 coded HO with a 611 (hood scoops/pans) as an all inclusive package (348/611 combined), but remember this is NOT a true "Ram Air" car as the engine was the same as an HO.
Then take a gander at the powertrain chart to see the difference in RA and HO for 68.
