Add water, wine and spices to poaching pan and place over low heat. Bring to a simmer just below boiling point. Rinse and dry fillet, then place skin down on poaching rack and lower into poaching mixture. Cover and simmer until done, approximately 20 minutes, depending on size of the fillet. To check, poke gently with sharp probe. If it passes through readily, the fillet is done.
Remove poaching pan from heat and allow contents to cool to room temperature before removing fillet. Lift cooled fillet from pan and allow to drain a few minutes. If tiny pin bones are still present above the position of the ribs, remove with tweezers. Carefully transfer the fillet onto serving platter and peel off skin.
In a mixing bowl, combine ranch-topping package with sour cream. Follow package directions. Spread uniformly over the salmon fillet to a thickness of 1/8 to 1/4-inch. Slice cucumber into 1/8-inch thick rounds. Start at slender tail of fillet and press individual cucumber rounds gently into the dip with each vertical row slightly overlapping the previous row to create "fish scales." Continue with row after row toward the head, until fillet is completely covered. Cover with plastic wrap and refrigerate. Serve cold.