IMHO - Above all put your RC receiver in the best possible place so that the antenna's are not obstructed in any way from the radio transmitter..... then work around that in the placement of other components.
In general the RC receiver needs to be close to the edge of the MR bottom plate near the back.
I put my Naza, radio, pmu etc all in between the two plates and in close proximity to each other and have no issues.
Most issues come from added on devices, in particular the GoPro camera and FPV related items due to difficulty in confining emi/rfi at the source.
How close can you put your other electronics to the Naza. My F450 is currently dissembled before I rebuild im wonder if there are problems with placing Futba RX, the VU, 5.8ghz video TX or small video battery on the bottom plate around the Naza. I want to keep as much weight to the center and keep space available on the small F450. Im thinking of putting the Futaba RX on the left of the bottom plate right beside the Naza to also block light from it but sure dont want any loss of RX TX range or Naza problems ect.