Roof vs Hitch Ski rack (+ Thule Quest Roof Cargo Bag)

[Gfolo19]

Hey guys I searched but didnt come up with much...

This is my 3rd QX4 but first time on this forum...

I have 03 Qx4 with hitch bought THule Parkway Parkway 958 (2 bike hitch Carrier).

I have the Thule 846 Quest Rooftop Cargo Bag also if I'm carrying a lot of stuff.
•Measures 32 x 18 x 40 inches (W x H x D), and has a load capacity of 13 cubic feet
http://www.amazon.com/Thule-846-Quest-R ... +cargo+box

I'm debating whether to get the Thule 9033 tram (which attaches to the Bike Rack)
http://www.austinkayak.com/products/952 ... mazon-pads

or Thule pull top.

http://www.amazon.com/Thule-Universal-P ... d_sbs_sg_1

What i want to know is if I could fitt the Quest Rooftop Cargo Bag (32 inches wide) & the Pull top ski rack (39 inches wide) which is 73 inches total on the stock roof rack? I assume not...but is there a ability to add another stock cross bar and off set them? so theiy not side by side?

Im concerned about weight on rear of vehicle and the rear sag.

This just came up in my other search...
http://www.carid.com/1996-nissan-pathfi ... 14117.html

thinking i should just get tram attachment and the rear air bags and call it day...wanted to get your take.

cheers have a good weekend.