I rear vent my woodstove directly into my fireplace, then use a 90 degree tee up into the flue. I'd like to close off the front of the fireplace now with a piece of sheetmetal and have a hole in it for the stovepipe to go through. I have a drawing with all the relevent dimensions sketched out and plan to take it to a local sheetmetal shop a friend recommended. My stovepipe is doublewall, even where it will go through this plate, and has a 6 1/4" outer diameter. I probably should have them cut the hole a tad oversize to give me a little wiggle room. What are some strategies for covering up any excess gap this hole creates around the stovepipe? I'm thinking I'll have a 1/16" to an 1/8". I've seen some round rosette things (not sure the right name) but now can't find any pictures online or products liek this to see if any are made for my 6 1/4" OD stovepipe. Has anybody done this bloc-off plate and wish they did it differently onece they were done? I plan to fasten it with just a few screws so I can remove it easily for inspection and cleaning. Thanks!