[CW] Restoring a 1943 Tin dataplate

[stan levandowski via CW]

Hi all.  I'm restoring an old Vibroplex and when I got to the tin plate, 
I started with the least abrasive method (soap, water, toothbrush) and 
progressively became more aggressive - vinegar and water, Simple Green , 
Coca-Cola, Brasso,  and a metal polishing paste.  Overall, it looks good 
except there is still the darkness (dirt,rust?) in many places like 
inside letters and numbers.



Does anyone have any suggestions for further improvement? 


73 and Season's Greetings,
Stan WB2LQF