73 olds delta 88 conv. 4 bbl H series horn
 

horn inop. replaced, still inop. when i press horn the relay on the firewall (center, top) clicks. it's adelco remy but there are no #'s evident. when the alarm was installed, the installer ran the power for the alarm horn to the relay. i don't understand why the alarm horn works but the car horn doesn't. any suggestions? can anyone identify the relay?