I've had this issue with a build and the way I went about it was mounting one of these slip ring deals to the end of the chassis, so that the bottom half of the hilt could spin freely without worry.(mostly, still a tight space so still be careful) They come in different wire amounts and sizes, I did have to shape this one down a bit to match diameter but it works!

https://www.amazon.com/dp/B00QSHPIHE...roduct_details