I've driven to San Diego each year for the past 6. I cross at Coutts/Sweetgrass. Stay on the saqme interstate all the way there. I head south to San Diego at San Bernadino (I think) so not sure about getting into Anaheim. That I'll figure out this August as we're going there first.
As for the hours I think it may be a bit more than 22. I drive faster after I cross the border & think its close to 27 hours to SD.
I cross Friday after work & overnight in Great Falls 5 hrs, next morning we usually pick up some groceries. Stay in Provost, Utah Sat night and late next afternoon or early evening we're in SD.
We'll stop at a big rest area in Idaho, make a sandwich and go for a walk. It's where the lava flowed thru, can't think of the geology part right now, very interesting tho and there are 2 different walks 1/2 hour and 1 hour. I like the rest stop heading south more than the north bound side.
On the way back we'll stay in Mesquite for a cheap room and hang out at the pool for a few hours. 20 mile east of Idaho Falls there is a great place called Bear World. Well worth the few hours to go to, especially with kids.
Not a whole lot to do as we're mostly in a hurry to get there and on the way back it's a bit more relaxed. We stay in Great Falls to do some shopping before we cross, no sales tax.