The local chamber of commerce in my Seattl neighborhood, Ballard, sponsors a seafood festival each year. They always serve thousands of folks freshly smoked salmon. Their method is pretty simple and I share it with you for some inspiration.
They've built large 4-sided metal ovens that fold up for storage. They stand about 3 feet tall and each long side is about 4 feet and the sides about 3 feet wide. Inside they've welded simple brackets to hold heavy-duty diamond pattern wire racks. They build a small file of alder wood on a bed of sand and let it start to smolder - two fellas life the boxes into which a couple of these wire racks have been placed and loaded skin-side down on foil, dozens of chum salmon...and place the box over the smokey fire. A simple metal lid fits over the top...there are a few holes in it to allow smoke to escape.
The results is a properly cooked whole salmon (I asked about the use of chum and one of the long-time cooks said it was because the fat content allowed a greater margin of error) they carry the box to the service line and life the salmon out on the foil, cutting it into service pieces.
Hope this helps inspire your effort!