Biglake may be on to something there. It looks like a compact pickup like an S-10 or a Ranger.
I'd focus on the line around the box at the top of the fender. That looks unique like it could be a spray in or drop in liner.
There may be some glare from a chrome bumper, not sure.
There's no apparent rust or dents.
Look at the top of the tailgate. Is that one of those tailgates with a fold down ladder step? What are those points coming off the top rear of the tailgate?
You can't make out the fender decal, but you can make out how tall the decal is in relation to the line where the fender meets the bed rail.
Given how late it was, my guess would be they live nearby. Outside chance they could be weekenders as well given it was saturday night.
I'd do a little recon "after work" by driving around your neighborhood and looking for those clues. Then turn it over to the CO or sheriff. Without any tangible evidence beyond the pics, they may give you a case number and just "file" it. Noon time opening weekend you'd get a lot of looks at the trucks in the neighborhood. Even if you can't catch anyone, if the sheriff asks the right person some questions about trespassing and mentions their truck fit the description, it could be the shot across the bow that's needed to end that behavior.