I agree with the 3-4" tomic but not the speed or down rigger.
Troll the hell out of em (3mph). Put them on the top and about 150-200ft back. The hottest colours are 256ii, 231iirn, 700, 700ii, 800, 800ii, 801 and 402. The cutties are spawning and the kokanee are going after the eggs. Also at the same time, the salmon fry are starting to come out of the creeks.
If you want more and just as good or better addvise go talk to the guys at Cowichan Fly & Tackle.