Thanks for Your replies.
So we sterted to strip the car a bit.
Front grill
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Sirens <Polish production - if somebody could show me how the original looks, I would be very grateful
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Guess something lived behind this headlamp
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Newer rekord emblems :/
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After stripping the paint in some places we got to this, that the car used to be silver probably at the beggining. On the back, we found the black paint <as in Sprint>. No stripes on the car thoug - could anybody write if the stripes were painted, or these were some kind of stickers <I'm talking about the two black Sprint stripes going through the whole car>

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