Back Glass 'Leopard Spot' issue

[Pauly540]

I have previously ask this question in 'Restoration', but maybe that was the wrong place.
My Wms 'Space Shuttle' back glass is suffering with bubbling.
I'm about to triple thick the flaking at the bottom of the glass, but can anyone suggest how to reduce the leopard spots? Is it just simply applying cling film and weight, during the triple thick method 

Any suggestions would be gratefully appreciated 

[Retropin]

The paint has come away in blobs... triple thick it now and it will prevent the blob edges from cracking.
As for the blob effect.. there is nothing you can do to it that wont possibly make it worse

[Strangeways]

The paint has come away in blobs... triple thick it now and it will prevent the blob edges from cracking.
As for the blob effect.. there is nothing you can do to it that wont possibly make it worse

+1

You can only arrest the bubbling by applying triple thick.