Difficult question, with no information about the size of your network and IT staff. Start with making yourself and all the people in your IT team familiar with the protocol, take classes, read books, build a lab. The cheapest integration is when you do it while there is time, when you do it step by step,, learn as you go, use natural life cycles of your devices and applications, start where it is not so critical so you can learn without pressure. And maybe cheap in the long term is getting some outside help from people that have done it before. If your network is a lttle larger than just 50 computers, ,you may want to think about a clever addressing plan, about how to secure your network (probably a dual-stack one). So you may not have to re-invent the wheel.