i would suggest getting some 65 lb braid. Yes, you can catch Musky on 30 lb, but it wont stand up to the abuse of bigger lures, or bigger fish.
Spinnerbaits are a great choice when looking for active fish. If they arent responding, then try the grandma with a " twitching" retrieve.
Trolling the Jake is an option as well. Find the structure on your map, and troll around it. Buying a bulldawg or other soft plastics would be a good idea as well. ( medium size dawg for that combo)
There is no way to control what size Musky you might catch... Although on average, the southern half holds smaller skis ( and pencil weeds)
Most importantly, if you want to catch one, put in the time. First one is the hardest, but stick it out.
Good luck