Scotty, my 2006 Altima V6 feels like it's misfiring, but no CEL. I changed the plugs since they were overdue, but though it feels better, it still misfires. Is there any way to check for misfires other than pulling off the intake again?

I disconnected the coils one by one on the front 3 cylinders and the rpms dip as I would expect. I'm planning on pulling the intake (again) to swap the coils, then check that the misfire follows the coils where I can check the coils on the front side again when the intake is back on.

Is that the best/easiest approach for a DIY mechanic?

find a pro like me, we have dealer level computers that record every single misfire and show the area. Or, if you want to try for a vacuum leak, do this video https://www.youtube.com/watch?v=zMok2y05jNE