Jet Provost query

Guys

I know you all like challenge so….. Does anyone know if a bog standard JP jet pipe will fit a JP Mk4 or was it a special to mark fit? If so does anyone know the sect ref/pt no for a Jet Provost Mk4 jet pipe? Finally does anyone have a spare lying around that they no longer require?

I’m afraid my fading brain cells cannot remember much of my sootie fitters course which of course used the JP as a training aid. All I seem to remember form those halcyon days is the engine was easy to change and the Rose & Crown in Wendover 😎