Or you could just forget doing all the formatting yourself and use the msdb sys function dbo.agent_datetime(@date int no default,@time int no default)

so to get the run date and time

SELECT dbo.agent_datetime(run_date,run_time)

or to get the completed date time

SELECT DATEADD(s,DATEDIFF(s,dbo.agent_datetime(run_date,0),dbo.agent_datetime(run_date,run_duration)),dbo.agent_datetime(run_date,run_time))