dssur
+1y
The upper control arm bushings and balljoints were not made to carry the weight of the front of the truck. Neither was the upper control arm mount really, the factory upper arm is merely a locator for the spindle.
Plus you would lose the mechanical advantage of using the longer lower arm, your bag would either be twisted weirdly at full lift or drop, or you would lose lift, or both.
Does this mean it cant be done? Of course not. There was a truck a while back that used that setup, looked super scary. I think it was posted in the mazda forum. If it were me I would rebuild the upper arm mounts and use a tube arm custom made to carry the weight, with a better balljoint.