OK, your saying, "That's not a roll bar rack" and your right but keep reading. You see, I was looking at this custom made mini roll bar rack at http://www.off-road.com/tlc/tech/rollbarrack/ and I thought to myself, that looks a heck of alot like the dohicky called a Hitch Haul that I bought from Cabela's. The Hitch Haul is intended to make room in your truck or SUV by adding a platform behind the vehicle for gear.
So I went out to the garage and threw it up on the roll bar of my FJ40 and I'll be darned, it sat up on the Cruiser roll bar like it was made for it! The square tube it sits on that allows you to put it into the hitch comes off with a few bolts. Cost $99 bucks at Cabela's. I have seen them cheaper at other locations. It can be used on top of a Cruiser or behind any vehicle with a hitch. It will hold two Action Packers side by side or two big coolers! If you want to read about the Cabela's version go to: http://www.cabelas.com/texis/scripts/store/+/CatalogDisplay/displayPOD/CabFALL1998/CabFALL1998AhAGAA/XA926I
Happy Topless Summer Cruising!