We had two dogs (ages 4 and 1) at the time our oldest daughter was born (will be 18 years ago on the 21st). We did what you are planning - had the baby stuff out and accessible, and brought home a baby blanket early (I had a c-section so stayed a couple days) so the dogs could smell it. They really didn’t have any problems adjusting to be honest, although I’m sure it helped that I quickly got proficient at managing 2 leashes while pushing a stroller. The bonus with that is the exercise and mental stimulation of a walk helps the dog to calm down and the fresh air tends to relax the baby as well! We did the best we could to keep them to their regular routines and they were fine. Mulder (our 1 year old male at the time) absolutely LOVED our daughter - when we would put her on a blanket for tummy time he would lay right next to her. Scully (4 year old female) was less interested ... that is until she was old enough to drop food off of the high chair.
Good luck with everything!