Ifish 2, I think the saying "Too many lakes too little time" applies here cause there are literally hundreds of trophy lakes between Merrit and Kamploops. I consider a trophy lake with Rainbows over 5 pounds, so if I may suggest you check out a magazine called "BC Fishing - Freshwater Directory & Atlas". This magazine will inform you specific locations of lakes, road accessibility, weight(kg) and types of fish, etc. I have often fished the following lakes and had my fair share of trophies; Roche, Tunkwa, Bonaparte, Logan, Nicola, Lundbom, Lac Le Jeune. If your willing to shell out a bit of cash you can try the Douglas Lake Ranch, they charge around $75.00 to fish their private lakes but I tell you it was none stop action fishing for trophy sized Rainbows. Anyway, you chose one of the best months (May) to go fishing so I'm sure you'll catch some trophies.