Yes, the axle flanges are different from V35/Z33 to V36/Z34 and also different if open diff or VLSD. Is the diff from the '06 G35 open or VLSD, auto or manual? Are you upgrading the LSD to a mechanical? Search.
axle flanges
The "flanges" are what you're asking about. The "axle joint assy" are the rear axles that go to the hub.