Set up left spar for riveting as we had done with the right spar. Started riveting from wingtip in. No real problem with gaps between spar and W-606C. Riveted all of those rivets first. Began hammering rivets thru spar, W-606C & W-606D and discovered gaps again being made between spar and W-606C. Skipped the rest of those rivets and riveted all of the rest of the rivets on the spar.
