my problem is that it is not the upper collars that are sized, its the bottom one. The collar you must loosen first.

 

You gotta just hit it with a BFH...

 

there is not risk of damaging it? sorry for the noob question but by bfh you mean big ... hammer?

 

Big ****ing Hammer... Yeah.

Use a soft metal rod. The aluminum tube I found worked perfectly. You want to hit the ring hard. But you don't want to damage it. Since the aluminum tube was softer than the ring, the tube took the damage rather than damaging the ring.

 

You may have better luck with the coils off the car if all else fails. Since it's the bottom collar. A big enough plumber's wrench will grip it well enough to break the ring loose, this wouldn't work in the rear since there's less space.

 

Unless you have a vice, it will be harder to hold the coilover.