Nice job. Yes that's it. The larger blue wire is the one you want. Just don't go cheap autozone type controller. I went with the Prodigy P3 because I used to tow doubles and it could handle 4 brake axles. I took it out of my truck and put it in my motorhome when we made the swap. Prodigy makes a direct plug and play adaptor to plug any of there controllers right into your RV's plug.
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