Looks like you are on the right track to get a servo installed for sure. Installing the servo was the hardest part of the build for me and was incredibly frustrating but the end product/result was definitely worth the hassle.
There are a few vendors on here that sell servo kits. I got mine from JC27 and his sales thread can be found here:
[URL unfurl="true"]https://www.thedentedhelmet.com/forums/threads/fettinator-industries-consolidated-sales-thread.29084/[/URL]
Outside of this, I am no help lol Good luck!