Seeking Bluebirds

Fairly active backyard birder. Since this spring, a bluebird pair have been eyeing my yard. Altho I have no HOSPs around, I put up two bluebird boxes. Seems the adult pair had already nested elsewhere. A couple days ago, I saw a fledgling bluebird checking out my yard, perched from one of the mature pine in my backyard. I am hoping this one will pick my yard for next year's home. Bluebirds typically don't feed from bird feeders with seed. They like bugs! I keep live mealworms on hand and occasionally put them out, away from the feeders to lure the bluebirds to finally feed. As I place the mealworms out, near a bush. I'm using a hi-low whistle as my bluebird feeding call. Can't wait til they finally fly to the grub! I have resorted to printouts of mature and fledgling bluebirds at the feeder and playing audio of the typical scratchy sounding call and of fledglings feeding. Have some cedar and lexan on hand to make a proper feeder, after they start feeding from the dish.