IJM sells a kit for clearing clogged nozzles in the print head. Why not use that device to draw out ink from the tubing between the (stationary) carts and the (moving) dampers before installing the (flush or K7) carts in the R3000? If that were possible, it seems that far less ink would be wasted in recharging the lines.
I just realized that the print-head geometry of the R3000 is totally different from that of the R2400. So this may not be possible, let alone desirable.