Sadly (for modellers), "Ural" trucks have too many versions, which have both big and small differences. Also military and civil versions have differences too, and period of production too.
My friend in our town works at plant, which makes different machines for road building and for municipal engineering, using the chassis of different truck's producers. This plant uses "Ural" chassis too - see below images of those vehicles and their designations:
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- MD-555,
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- MD-432-02,
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- ATsB-12IIIA-01,
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- MK-10V.
And my friend (he is scale modeller too) has noticed, that every new batch of chassis have differences - at least small or smaller - from previous batch (almost every time).
Thus, it is too hard to build "ideal", 100 %-authentic model of "Ural" truck.
But You can try to do this as much as possible.
So, cabine seats - and here we can see differences too.
An example:
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It looks like more modern civil version of seat base.
But following two pictures shows early military style of bases:
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Driver's seat:
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These two images are correspond to period of production and to models of "Ural", that You have.
As for spare wheel holder - check Your e-mail box.