All I need now is to not allow updates to existing jobs

Any ideas?

USE msdb;

CREATE ROLE JobsViewer AUTHORIZATION db_securityadmin;

GO

use msdb

EXECUTE sp_addrolemember 'JobsViewer', 'johntest1'

DENY EXECUTE ON OBJECT::msdb.dbo.sp_add_job TO JobsViewer

DENY EXECUTE ON OBJECT::msdb.dbo.sp_add_jobserver TO JobsViewer

DENY EXECUTE ON OBJECT::msdb.dbo.sp_add_jobstep TO JobsViewer

DENY EXECUTE ON OBJECT::msdb.dbo.sp_update_job TO JobsViewer

DENY EXECUTE ON OBJECT::msdb.dbo.sp_add_jobschedule TO JobsViewer

DENY EXECUTE ON OBJECT::msdb.dbo.sp_delete_job TO JobsViewer