I always used to "CAP" off any areas that i did not want getting "Acid Dipped "
Here is X valve prepped ,cleaned & ready to go to the acid bath :
And after :
One i had done for G.H. many years ago
Notice the two shades of green from the body ,to the valve
Thats due to different grades of aluminum
Usually 6011 & 7011 , valve being a better,denser grade (prolly same as barrel)
This creates a "shade difference " That can USUALLY be corrected
90% of the time ,and with alot of patience & practice
This one i could not get exact ( shade that is )
So being as it was a dust digi camo feel , it grew on me and i decided to leave it