I know this is an older thread, that said
When I bought my 223 load master kit, lee mixed up my dies, including the wrong charging die and a quick trim die, I know a lot of people either leave 2 empty or advise putting a resizer there with the decapping stem removed, but I've been using the quick trim die as an alignment die, it adds almost no resistance and as long as I don't spill powder in my primer assembly or let a crimped case through it runs flawlessly.
FWIW when I do get around to getting another plate and doing a 9mm conversion, I'll have another quick trim die in 2.