OP, I'm going to give you a couple of websites of folks who would likely be willing to help you. I believe the cone and a very sharp knife is the best way, but It's not easy and takes a bit of skill. Tubing cutters also work well but again I don't think that fits you. I'm still an amateur and have only put down a few hundred meat birds. When I do it right they fall asleep in the cone and never feel it. When I do it wrong I feel terrible.
So here are the websites look for someone near you.
https://apppa.org/
http://www.spnusa.com/
both groups know how to do it painlessly. It takes patience and the right cut. I really don't think you're ready to jump off that bridge. If I were closer I'd offer to help.
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