They are a direct fit. I use an old 500mm smooth twist impact barrel in mine sometimes. This barrel was made before the Crown was ever in production and does not have a liner.
But to address your original interest, the tensioning kit would require a custom shroud to work, I'm pretty sure. Being that they are very different in lengths. I am using a carbon tube on the barrel that is tensioned via the moderator or 3d printed thread protector in this instance.