Everyone. Seriously, find a car that weighs 3,000+ lbs that runs a 100 lb/in wheel rate. Nothing does and nothing has in at least 30+ years. Most modern cars in similar weight categories are much closer to 200 lb/in.
The moment you put radial tires on the car, the factory bars should go in the trash. Even for cruisers. The only exception being dedicated drag cars.
Yep, doesn't even need to be that. Radial tires should be the determining factor.
If they're RCD Bilsteins I believe they are rebuildable. You might try contacting RCD and see what they say about it.