hiya petro, that looks better
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ok for the chipping you can mix silver with gun metal and take a small brush and just gently drybrush corners with it and make some really small irregular shapes on the vehicle just watch out that you dont over do it.
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generaly you scratch : corners, places the crew walkes a lot, (climb aboard) the gun shield due to the hight it probably would hit some branches.
after that your are like done, with another cool model
(thanks for sharing with us that there are (almost) no bad parts in this kit.
maybe nice during winter time for me to build