How to replace window motor on ford escort 1999?

Just trying to get a bit of advice before I start this job. I have a ford escort mk V (1999)

The cables snapped in drivers side window motor so will have to replace the window motor assembly. Presently the window is closed position and I have removed the inner door liner ready for job.

What do I need to do other than drill out pop rivets to release motor and rail brackets?.

Is it best to lower the window or best to leave it in closed position? Need to get this job done quick due to weather!

Thanks in advance for any replies