Coilover springs do not fit into the top of the tapered chassis cavities where the rear shocks mount.

These extended-length upper spring perches solve the problem by moving the spring down where it doesn’t contact the chassis.

The perches are available for 2.25″ springs. Or you can add a 2.25″ to 2.5″ adaptor to use 2.5″ springs.

They have a 14mm ID to fit Von shocks, Bilstein RSR, HD and Sport shocks, or MCS coilovers.