You can get a good stock fitter to try to fit you, in their place. Then go somewhere and shoot and see how you do, that is, collect all the data you can by yourself, and go back and forth to your fitter until you get it right or comfortable.
Or, you can go to Allems. Nobody is an expert in everything, and maybe John is not the premier stock fitter, per se. However, he is a longtime championship ATA trap shooter, multiple PA Top shooter in many categories, Captain of PA teams, etc. (how many fitters can say that?) He has worked on stocks of all types for decades, & chokes, and barrels and and and.
He has a trap field on his property, and he can watch you and make adjustments for you on the fly, to help you get a great result that day, that you know is good. He can ste the trap and work on certain targets to get you smoking on your good hits. If necessary, you can fine tune it later, but you'll leave Zionsville with confidence and learn a lot along the way on live targets. It's the next best thing to traveling to a top notch clinic, and more personal attention.
Make an appointment with John; tell him what you want to accomplish, & spend a few bucks for 2 hours trap time & advice, and it will be money well spent.
That's my opinion, that's what I have done, and I am pleased.
Best of luck
js in PA