Hello,
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Just picked up my new straps from the dealer today. Where are the two shims supposed to be installed?

Thanks for the help!

Well, with no answer (little patience) I threw them on. I put the washer in the same place as the factory ones were. That was between the latch bracket and the tailgate. The factory ones looked more like retaining clips to make assembly of the truck easier. The ones I got with the new straps were regular washers. I did not see any better place and I figured they would take up the same space.
<?:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" /> End result is that the tailgate opens and closes properly. The right strap is a tad shorter than the left, but it will work fine.

I also noticed after the dealer installed my new straps that the right one was a little shorter than the left...

The shims go right under the shoulder of the bolt. Its a spacer to keep the strap moving free when tight.