Again, like the Tu-tu net that I found to be ideal for chickenwire on helmets, I think that I found the suitable substitute for the ultra thin lead sheet. A travel towel

In the camping supplies area of a store I never really go into I found a lightweight travel towel.
Its like chamois cloth & is the size of a normal bath towel but thin.
Had the look & feel of what I needed & was $5 bucks (thats about 2.20 quid

Cut it to size & covered the inside with undiluted PVA glue. Then the fun/shit started !!
Must have had some form of contaminant on a bit of it because a section just would not stay stuck to the brass ring

Exercised my right to lose it & busted out the super glue.
Sorted.
Also ran cable conduits to the front lights & added a drivers plate track retainer bar.
Really is a practice run for the StuG but without side skirts.