When porting this intake, should the small dams in the back of the plenum be removed? The RB Holley S/D doesnt have them.Is there a fuel distribution issue with the B intake?

I would leave them. I have no dyno/porting exp (ex for minor port matching/contouring) but I think the odds are greater that even with porting that their bennie would not be eliminated.

I agree, work the plenum to port roof transitions, particularly where the cylinders fire consecutively (2-1) and (5-7). Really a flat floor in the SD design, I never found any power there.

Talk to member GY3, he bought my RB manifold that he runs on his 500 stroker, everyone whose ever done my plenum/runner mods to a SD seems to pick up at least an easy tenth tenth and 1-2 MPH. Even more power available if you can run a carb spacer and jet up a tad.

Leave the floor danms because Holley did the work to balance the intake where ma Mopar told you to add them in on there intakes