How to change the spc on a sprint iphone?

I'm trying to activate my sprint iphone to verizon but i need to change the spc and i don't know how to do that

You can just get it flashed by a professional where modding firmware isn't a part of flashing. I had my phone flashed once remotely to Verizon and it didn't involve any modding. So there's no chance of bricking the phone. You can mail this person (arghyle@rocketmail.com) who can help you with your flashing.