Combine the juice, syrup, soy sauce, garlic, onion, and ginger. Stir, let it sit for five minutes, and then reserve about 1/2 c of the marinade to be used as a final dressing.
Cut the salmon into bite-size pieces, one inch or less. Try to remove as much skin as possible without wasting the good stuff. Let the pieces soak in the marinade for 1 to 1 1/2 hours. In the meantime, you can preheat the over to 350 (I've learned mine really does take half an hour to get to temperature) and take a break for a while
Start the noodles so that they can finish about the same time as the salmon without causing a crisis, and drain when done. If you expect to reheat the dish before serving, you might want to cook the noodles to a softer stage than al dente.
Prepare a shallow, oiled baking pan, and place the salmon pieces on it. Allow the salmon to cook 7-10 minutes, until they're just flaky; don't overcook.
Remove the salmon from the oven, combine the noodles and salmon in a large serving dish or casserole, and toss with the marinade that had been set aside at the beginning. Garnish with some scallion snippets, paprika, or parsley.