Yea, I was scared of screwing up my pretty new block. Swiftech could (rightly) deny warranty for screwing up the threads when theirs worked perfectly well. Not that they would, but they could. Better safe than sorry.

If it helps, here are photos of where they stop:

Copper fittings.
D-Tek high flows.

The Swiftech fittings screwed right in all the way by hand.