Georg at Valley Hybrids (Mud vendor) sells Terrain Tamer. I have had this lift on for over 5 years and it works well. No flattening or stink bug and I have logged a lot of off-road miles.
When you do you heater core, mark the orientation of the inlet and outlet tubes and have the shop braze them to the core. This will eliminate the “O” rings that will eventually start to leak.