Il-2KR photo help!

[Dark Green Man]

I believe there were subtle variations in 'regular' Il-2 wings, most of which would not be noticeable in 1/72nd scale, so I would not worry about that too much.
the real trick is that all the model companies that do kits of the Il-2 in 1/72 all do them slightly different.
this creates differences in size, shape and fit, meaning that you may have some problems (maybe many) in this conversion.
your other major change is that the Smer kit has external aileron mass balances molded onto the lower wing , these will have to go.
(those 'rails' out near the wingtip along the axis of flight)
these were only fitted to early single-seat machines with all-metal wings , internal changes to the wing made these obsolete later on and did not appear on any two-seat machine.
if you wish to model a wooden outer wing then you will have to fill in and sand the unneeded panel lines.

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