You replaced the soft line going down to the rear axle from the frame with a hard line?
Replace the rear cylinder again on the wheel that is acting up. If the brakes is burning up, it would seem there is either a mechanical issue with the cylinder which is not allowing it to release and...
I would start with replacing all the soft lines if you haven't yet. They are cheap from dealership.
Talked about it in this thread
https://forum.ih8mud.com/showthread.php?t=79304