These are the instructions that were included with MP-S Series answering stations.
MP-S Instructions
AP-M Operation and Installation Instructions
MP-S Instructions
Adding External Signaling to an AP-M Answering Station
Adding an LE Series Door or Sub Station to an AP-M Answering Station
Using an LE Door or Sub Station with an MP-S Answering Station
Adding External Signaling to an Existing MP-S Answering Station