Stovepipe connection

This is a great site. Thanks for sharing your knowledge. I've searched all over the net and can't find this one. I'm connecting an Englander woodstove with a 6" collar to a chimney with an 8" (inside diameter) clay thimble. I noticed that NFPA 211 requires the stovepipe to be inserted to the flue liner. I was going to use 6" stovepipe increased to 8" near the chimney, but 8" stovepipe is too big around to insert. I considered buying one of the 8" telescoping stovepipe sections and using the smaller diameter piece to slide into the thimble. Any suggestions?

Here I'm replying to my question... I just remeasured the clay thimble. It is a little less than 8" inside diameter in some areas, it's not perfectly round, so an 8" outside diameter piece of stove pipe won't work. I haven't seen "connector pipes" listed for sale at any of the online sales sites.

You Miss understood the directions. Use the 6" all the way but when you make the connection it has to be inserted to the inside of the clay flue. Not 2" short or 2 inches past. flush with the inside of the clay liner. A 6 " metal flue is fine with 8" clay liner
good luck Keep us posted how it works as we have not heard from many who bought Englanders