I've done it to 3.5nm which is about 31inch pounds, I'll see how it shoots here and then tighten it a tad if needs be. The trigger guard unit is plastic, the stocks synthetic, I don't want to over do it.
Hopefully this thread is now useful in the future to be found by anyone else who is struggling with getting the action seated.
I have to be honest, this stock is a pile of crap. it's not as good as the base synthetic stock on the CZ 452!