If yu apply tooo much pressure they DO break away like that, suks i kno. The top one yur referring to correct, kinda chrome and the base id sorta plastic? Well if the head broke off to where yu can still remove the spacer and bushing, the easiest thing would be to remove the unit frum the car. When out yu sould be able to remove the remainder of the " special nut" from the collar of the unit.