I manufacture a Delrin bushing that does not use the original outer shell.

If the torsion bars are installed all the way forward AND adjustable strut rods are used, they won't move.

My opinion on OE bushings are they were junk when new and are worse now due to offshore manufacturing. I see these blown apart on a regular basis even with limited usage.

Stabilizing the lower arm and strut rod are so important in creating a tight suspension, but it takes the purchase of some pricey parts.