So, I have the above chimney / stove I'm installing and the "extension pipe" that goes in the ceiling support (8" stainless from ceiling up, 6" black pipe from stove to ceiling) only seems to fit with the 8" side down. what am I missing!? I've tried everything to make it fit 6" to 6" and 8" to 8" and it flat out won't fit. If I install it the other way round it fits great.... I've searched and I can't find any answers to this. Anyone able to help me figure out what I'm doing wrong? Everything is ready to go - hole in roof and snow this week is imminent! Help is very much appreciated!