There isn't a lot of info on them. I was interested a while ago and did some searching. This thread on the FJ forum is really all I could find with some good info on toolboxes that attach to the stealth. Not sure they are Gobi though.
Can't remember guys full name but it's swimmerdude? He has one mounted on his sunroof insert I think. I just had a kid so couldn't justify buying one. So I built one bigger out of stuff I had and mounted it on the back section of the rack.
im sorry but i dont like my toolbox. it doesnt keep water out well and even though it has a lock it can be broken into with a screwdriver. you can find any weatherproof toolbox and secure it to your rack for less then half the price. and why the heck is is mine on an angle? lol.. anyway i put mine close to my ladder so i can get to it quickly. im going to replace it with something better soon and just us this as a ammo/gun box for the garage.