Woodstove Chimney question

[JCVS]

I am installing a rear-vent woodstove with a 6" collar. The chimney is 6" Duravent which runs down the side of the house to a "T", then horizontally through a thimble. Per the specs, the Duravent must run 6" past the interior wall into the room. Due to conditions in the room, the stove will be set 12" from the wall, and therefore 6" from the end of the Duravent. Question - is there a slick, quality way to go the addditional 6" with the Duravent and connect it directly to the stove? Alternatively, I can adapt DVL to the end of the Duravent, but how would the DVL connect to the stove?

Thanks for any advice. JCVS