Just sorted the counters for Invasion 1944 into a repurposed West End counter tray. Registration was perfect. These counters are cut along the center of each side, and the cutting goes into the counter tree, thus I recommend slowly separating the counters. The tree will come apart in many small pieces. The counter sheet includes 3 armies, U.S., Wehrmacht, and Luftwaffe, with about a fourth of the sheet status markers, and a brand new turn marker, printed that way on both sides so it isn't mistaken for a blank counter. Of course, Avalanche never gives us blank counters.
This seems like the same way the Broken Axis counter sheets were done. I had very little trouble with them (some paper tore off at the "nib" of one German 81mm counter), and it was weird to see the entire counter tree as part of the "puzzle", not just the counters.
Larry, you can purchase blank counters from Legion Games (.6") and Pacific Rim Publishing (1/2" and 5/8"). I have for playtesting but we don't use them often because we can almost always borrow units from another nation when needed.
For the most recent counter sets (for me, Broken Axis and AaD), I've found running a thin sharp knife blade, e.g. a Spyderco Dragonfly, along the seams helps with the process.