If you have Poly or Delrin LCA bushings the pivots/pins don’t need to be torqued at ride height. Those bushings rotate on the pivot/pin, so it doesn’t matter where they get torqued.
The factory rubber LCA bushings need to be torqued at ride height because nothing spins or rotates. All of the suspension travel is flex in the bushing. Because of that the LCA needs to be roughly in the middle of its travel range, so half the rubber flex is up and half is down. If the pivot/pin nut is torqued with the suspension on the bump stops, the rubber can’t flex far enough to cover the whole range of travel and it will tear.
As far as keeping the pivot/pin from spinning, I use an impact. But a lot of the aftermarket pivots come with a nylock nut, so that doesn’t always work. The factory used a crush nut. So in those cases sometimes you have to grab the pivot by the shoulder from the LCA side to keep it from spinning. If the suspension isn’t fully assembled you can slide the LCA back to get the room to grab the shoulder, don’t damage the surface the bushing rides on. With Delrin or poly bushings you can just install the pivots/pins by themselves and torque them like that, then install the LCA if you want.
Another option would be to just use a lock washer and a standard, non-locking nut. With that final torque on those nuts having them loosen up is pretty unlikely. You could use Loctite too. That way you’d be able to spin the nut on with an impact and when it hits the lock washer it should grab and not spin the pivot.
