After alot of messing about I finally figured it out (if anyones still interested!) I thought Id share somewhere as theres zero information anywhere on how to do this.
Once youve removed the chinstrap clip you need to feed a very skinny but relatively stiff metal rod (a screwdriver wont do, I used a butterknife I ground smaller in width) between the strap for the suspension webbing and the clip that is now visable (basically where the first clip you removed came out of).
20mm from the bottom of this tab is a lip you have to get past but its tapered slightly (towards the strap) so whilst it may seem tight, provided your tool is thin enough it should squeeze through no issue.
Bang in the centre and another 10mm up from the lip, is another tab that when pressed in, will let you slide out the headlight clip on the top of the helmet.
This takes the tab you originally exposed with it and is then fairly obvious how the next clip is undone that releases the strap. Its a two prong tab that sits either side of the tab you just removed and can be jimmyed either side with a small flathead.
Absolute ballache but its fairly simple once you understand it. Just dont give it beans with the tool and try not to go any further than 30-35mm or youll hit a delicate piece of plastic that the headlight clip is locked into the helmet with. If you do damage this dont worry too much as once its back together it all seems to hold itself pretty sound however youve most definately fubar'd your CE rating on the lid. You dont need much force for the clips to release so if you find yourself competing with Ronnie Coleman, somethings going wrong.
LIGHTWEIGHT BABY! 🤙
