I rub the potatoes with OO then put on some Kosher salt and coarse pepper,
I have used some rub before also.
I don't cook to a temp I just smoke till there soft in the middle, I check with a fork. If the fork goes in easy there done.
And they are real good... Love Smoked potatoes.
Do them all the time except we rub with butter and roll in some spices. I give them about an hour in the smoke then wrap them tight in foil for a couple of hours. Maybe a half hour out to firm up the skin. Test with a fork to see if they are done. Around 3 to 3 1/2 hours for the big uns. We do baked and sweet.