G.B.
You don't do away with pull ups at bedtime until they are dry a couple of weeks with no accidents at all.
Pull ups are not diapers. They are shaped like underwear so the child can learn to pull them up and down and YOU don't have to bleach floors and clean up poop all day. If you really want your floors and furniture to have that stuff on it then that's different. I choose to have less laundry and less cleaning and have a more enjoyable time potty training.
It's a personal choice of course. I will say though, the extra cost of cleaning supplies and all the extra expense of load after load of laundry will cost more than that box of pull ups. Plus your time is worth something. He'll be happier spending time with you instead of you living tied to the washing machine with all the bed linens he'll wet night after night until he's much older.
There is no such thing as night time potty training. He will stay dry when his brain turns on the signal to stop making urine when he's asleep. Once that happens he'll go to sleep and the urine production will stop. Then he will be dry from then on.