Ah, Nadolol...my favorite drug to hate. I remember it well from two decades ago.
It's amost UNIQUE in it's lasting ability with a half life of 72 hours. HORRIBLE if you have a reaction because you suffer and suffer and suffer.
With that half life I think no weaning is necessary, it's self-weaning. Personally, After I could barely lift my legs from weakness I stopped cold turkey. There were no palps or high heart rate.
(I was taking 40 mg.)
It's terrible to take any drug that takes like 10 days to reach steady state with the first day's dose still going strong.
I've just taken a 3 day course of Zithromax that does the same thing, but 3 pills and done is a nice way to take a powerful antibiotic that works for 10 days! It worked beautifully in a couple days (bronchitis/pneumonia) but I pity anyone who has a reaction to that drug. You'd need a blood change.