iMac 27" Screen Problem

[Bettz1]

Hi all i've been reading a few threads on screen issues with iMacs from 2011.
Just wanted to post a few pics of my problem.I'm out of warranty by 5 months but im fairly confident when it comes to messing with pc's laptops etc.I'm hoping this issue is just dust ???,the issues in the top right.

 

[Tankmaze]

yup it is dust unfortunately

https://forums.macrumors.com/threads/1101370/

 

[Bettz1]

Thanks pretty easy to sort right? suction cap lift screen off wipe away

 

[Bettz1]

Right finally got round to doing this & after lifting off the glass and cleaning the screen the marks are still there it looks like it in the lcd any advice?

Updated pics with glass screen cover off

 

[Tri-stan]

It could be behind the second glossy panel?

 

[Bettz1]

I've just found this https://forums.macrumors.com/threads/1101370/ am i right in thinking i just need to follow this guide?