I think Tinstaafl is right - try doing the training in chunks. But it should be possible part-time and at weekends.
The problem will be finding somewhere to do it. My guess is you'd be better off going to the smaller schools or clubs who do CPL as well as PPL. A good friend of mine did it all at weekends with no problems but he was friends with his instructor, so the instructor came in on his weekends. The club mentioned in a previous post sounds good - you could also try Aeros at Glos or Old Sarum near Salisbury.
If it's at all possible, take a week's leave to complete the training, so the end of the training has continuity.