Nice attention to details Simon!
I really like your build and love watching the progress.
Dremel and chemical metal, my kind of build!
Looking at your excellent muzzle I have a
little tip for you.
The washer between the muzzle and the barrel ring was dented into the square dug outs to prevent the muzzle to turn loose.
Please look here at the Vimoutier Tiger I
And the Saumur Tiger I

(bare in mind the Saumur muzzle is mounted almost up side down for some unknown reason.

)
The same dent was seen on Panthers as well as Tiger II but is not that well known...
You can have the first 1:6th tank with that dent as I have never seen anyone done it before.
It is all in the details!
Kind regards
Kent