You're doing an awesome job for the first time, don't sweat it.
Yeah, that is my point with the first sanding of the clear, it's the same with primer, you have to make sure that is perfect before you proceed.
This is a very important little tip, "Never ask the product to do too much."
It's a thought that should always be in your head as you do this stuff. All the way from the bondo, don't ask it to fill too much, right? The primer, don't ask it to fill too much, don't leave coarse scratches in the bondo, don't leave pin holes, don't leave an poor feather edge expecting the primer to fill it! That is a huge no-no. One of the first things we would do to correct those scratches in the primer or pin holes or what ever is to apply the primer heavy right? Well not you have primer full of solvent, the KILLER in any paintwork is products full of solvent sprayed too wet. It shrinks, it wrinkles, it dies back, it is without a doubt the number one reason for failure in paint jobs, excessive solvents from applying products too heavy or too short of flash time, or too many coats etc.
Applying a "skim coat" of polyester putty over your filler work and never sanding that with anything coarser than 180 will all but eliminate sand scratch problems with primers. Any primer can fill those 180 scratches easy, end of problem, you aren't asking it to do too much.
But really, your truck, for a driver, are you kidding, that thing is going to be awesome!
Brian