I have a 04 Yukon with a 2/4 but wanting to go 3/5. I have the hardware kit,belltech lowering shocks and free travel mod. I'm looking to buy a nice riding set of 5 inch lowering springs for the back. Not looking to spend anymore than around $170 for a set of springs, I have heard of ppl using tb springs but Dont know the part number, any help would be appreciated