As Bunjin stated the, C clips are for the snap up brackets. I know this appear "wiggly" when no weight is on them, but they work well. When the weight is pulling on then, they do not wiggle and stay put.
The 2 pins, can you post a picture of the hitch? Reese made a lot of hitches over the years. They "might" be keeper pins from an older vintage round bar hitch to hold the bars into the head. Have to see the hitch to be sure.
Current Sunlines: 2004 T310SR, 2004 T1950, 2004 T2475, 2007 T2499, 2004 T317SR
Prior Sunlines: 2004 T2499 - Fern Blue
2005 Ford F350 Lariat, 6.8L V10 W/ 4.10 rear axle, CC, Short Bed, SRW. Reese HP trunnion bar hitch W/ HP DC
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