attic insullation shield doesnt extend to my decorative ceiling support

[Lure hobby farm]

I’m installing my wood stove with Selkirk pipes from menards. I framed my fire box and installed the decorative ceiling support and ran the pipe from the stove up to the decorative ceiling support. My box I framed sits on my sheetrock in the attic side and is flush with the top of the ceiling rafters. The ceiling rafters are roughly 9” (old 2x8) from a 100 year old house with layers of plaster and sheetrock. The problem I’m having is the part of the attic insulation shield that slides down to the decorative ceiling support is about 2-2 1/2” short. What should I do for this. I’m thinking about buying some sheet metal and screwing it to it to extend it. Any thoughts as I’m new to this game. Thank you.

 

[Riverbanks]

You got it, screwed or rivited, they should make a taller shield, insulation is getting thicker