Tunnel ram or no tunnel ram...

This is Indy tunnel ram without cover after initial cleaning. I was thinking about spacer under top cover but this is for future experiments. No room for anything in current setup.
I was asking about filling that void based on this plenum design.

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OK sorry I misread this reply. So what i have in that cavity is sloped in a similar way but, more importantly let's not assume that Indy designed this 'correct' either. You won't see all this 'correct' executed in any new tunnelram plenums.