Exhaust pipe insulation?
 

I'm building a Trim F-86.
I have some BVM heat shield and I've painted the last 10 inches or so with two coats of it.
Is that far enough? There's lots of space between the fuse and the front part of the pipe, but it gets down to 1/2 inch or so at the rear.
How about glass insulation wrapped around the pipe?
Or is it better to leave room for air flow around the outside?
It's a double wall SS pipe, so there will be airflow between the pipes.
I does have a by-pass too.

Thanks