I would say that you have things in your CV that should be in your covering letter and things in your covering letter that should be in your CV.
Employers like clear concise CVs so should basically only list qualifications and work experience. Keep it very factual. I tend to keep it to one page in total with work experience detailing where, how long and what postion and education detailing where, how long, exam title, grade.
Your letter should be concise too just saying you are interested in the job and explain which of your qualities help you fit the criteria and say you see the job as a way of challenging yourself and as you wrote, you have supplied CV and portfolio. I wouldn't go into lengthy details of where you see yourself and what you've done.
To save space I have my name central at the top with my address, phone, email below all on one line.
That's just my opinion
