I love this idea and it got me thinking. It appears that the shotgun shell you are using is a Bird/Buckshot. What if you use a Slug instead. Fore example you could focus on one topic lets say Fear since it is the mind killer. Pick one thing you fear lets say Spiders.
“I am afraid of Spiders”
“I think spiders are ugly”
“I think Spiders are Scary”
“Spiders creep me out”
“Spiders are dangerous”
“I will die if a spider bites me”
Then you would install new beliefs. What I am finding with this is that it is easier to get to the root of the problem/subject/belief. I would say it is more of a Laser approach :P.
“I am grateful that spiders exist and I am at ease when they are near me”
“Spiders are cool”
“Spiders are useful in this world and I respect their place”
“Spiders are beautiful insects”
“Spiders like me and I like Spiders”
Just some examples here. I am actually going to work with this one later today.