Looking to switch from my ashley 5660l to a harman xxv! No problem right? Wrong the damn exhaust outlet on the back of the harman is not even close to where the wall thimble is for the ashley. These means upgrading from 3inch to 4inch pipe to stay under the recommend evl. Unfortunately I cannot match the stove up to the thimble unless I want it to be off center and raised up on cinder blocks which is not gonna fly. So in order for me to replace this pipe out is a major deal cause it goes thru the roof. Id need a new hole cut with new flashing and the old hole fixed and retiled. Dammit i wish it was a standard where to put the outlet on these stoves. Anyway my question is about the pipe flashing on the roof. Can it be trimmed where the pipe goes thru to accept a 4in pipe? If this can be trimmed I can make this work and without cutting more holes in the roof. Has anyone come across this?