My 73 Ranger has that same roof rack. Four legs screwed thru the roof plus the four or five runners screwed thru the roof on the ends. I removed it when repainting the top and welded all the holes closed. It’s in good shape except for a crease in the back cross brace. Didn’t try to straighten. If interested I’ll take some pics, the plastic/rubber runners that sat under the rack are weathered and cracked and would need to be replaced. I was told by PO that it was installed by dealership in Los Angeles when delivered. But he also told me it was rust free. Haha.