Agree that CameralandNY is A+.
If you are sizing a rack at 600 near dusk with binocs, you will need to spend a ton of money and need a cart for hauling the tripod and glass. I would either look at sandbagging a min 70mm spotting scope at about 32x or buying a riflescope with a large objective lens and 25 to 35x top end. I have older Lecia 10x40 binocs (from Cameraland) and my 3x15x52 NF scopes are much better for trying to count points. There are much brighter riflescopes out there than NF, but you are looking at $1500 as a starting point for medium tier glass and $2500+ for top tier. You can get a nice spotting scope for a grand and I'd go for a straight vs angled as you will need to get on target fast with minimal movement. That said, the competition precision rifle shooters are opting for high power binocs over spotting scopes nowadays for spotting hits at 1000+ yards. But the cost of equipment doesn't seem to bother these guys, their guns weight 20+ pounds and they are only traveling 100' from their truck to the shooting line. If you are shooting at 600 yds, you probably have a pretty expensive setup already.
I'm trying to count points out to 250 yards. The problem I have using a spotting scope in a shooting house is transitioning from the scope to the gun quickly without making a racket plus the additional weight of hauling it in and out. There isn't room for a tripod so the spotting scope has to be sandbagged. Plus the best place for it is always the best place for my rifle. It is also hard to track something moving with a sandbagged spotting scope. Additionally, most tripods are not designed to pan either.
I have a monopod for my binocs and it works great for stabilizing the glass and panning is effortless. However, I seem to always bump something when putting them aside.
Finally, the big racks I see in an open field are usually not there very long and I don't have the luxury of spending a lot of time moving from one magnifier to another, so I have decided to primarily rely on my riflescope.
Good luck with your quest!