I do appologize, I meant 87 octane not 89, not sure where my head was at.
And yes, I know the GM Vehicles had two injectors in most if not all of the 305 and 350 motors as I have had both.
As for the cats, I kept the system and the mesh screen appears to be fine.
I do not spray the mass air with anything but the special cleaner for this due to the sesitivity of these units, always spray throttle body cleaner in any throttle body as they gum up after awhile
The van appears to have more power after the initial swap of the new cats.
Not sure yet if this is the fix or solution to the problem | 
