Actually, I think the surround on the 4th gen is misleading me, the part behind looks flat, so I think they are the same. You won't know if there any detail differences until you removed yours though, which I seem to remember is a bit fiddly...
Let me know if you need the whole thing or just bits...
Hey pal thank you for looking, arif has a 4th gen complete so I'll get that, then I don't have to worry if it's the same. But thank you so much for helping. Much appreciated. Chris