I've forced myself to set my system in 6.8 like I do in 300 BLK.
While charging cases, they are in the white tray. If you note the powder level in these cases, it is only 29.4 grains of Re10x.*
Grab a bullet, seat it and place it in the green tray. 90 grain Speer TNT, in this case.
Use the Lee Factory Crimp Die and place into case. Done.
I do posses more loading trays. But they are the "dirty" trays covered in case lube. I don't like that crap around powder period. The 40 trays are a handy, compact way to keep brass together. 9mm trays work fine for .223 Remington based cases.
*I now know what I did to screw up. Besides not putting powder into 4 cases and not checking the powder level before seating bullets. Note the height of powder in these cases- some are very near the top, others not so much. Hornady cases vary in weight by lot number. Of the 100 once fired cases I prepped tonight (primed with a CC450 primer) 20 weighed in at 117-120 grains. 80 of them weighed 127-130 grains. The lighter cases have more case volume. Meaning a lower powder level in those cases. Most of the last batch were of the high volume variety. Save for one. I fixated on that one, (#21 of 30) weighing the powder two or three times to assure myself it had the same charge. I then skipped to #26 and continued charging cases. And failed double check my work before continuing.
With 300 BLK I check every time. The powder level is so low in the case that it is almost never visible from an angle. I've done about 1K of them since the last time I loaded 6.8 SPC.