On mine (from tuff-trek so might be different), the bolts slide into the two tracks in the rail on the back of the awning and then fix onto the L-shaped brackets or directly onto a roof rack. They slide easily enough when putting them in one at a time but the entire awning didn't really slide on all four at once.
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I slid the four bolts into approximately the right place then offered the awning up to the brackets (requires two people) and manoeuvred the bolts into the right place to go in the holes in the bracket.
Rich