removing replication on SP

I have my own SP in the master database that had sp_MS_marksystemobject applied to it. It now needs revising but it cannot be renamed. It cannot be dropped because it is used for replication (apparently).
When I try to drop it, get message: Server: Msg 3724, Level 16, State 2, Line 1
Cannot drop the procedure '<sp_name>' because it is being used for replication.
Anyone know how the replication can be removed
use sp_MSunmarkreplinfo against this proc and then drop it from within isqlw.