Tree Replacement Thread - MISERY mod for S.T.A.L.K.E.R.: Call of Pripyat

I'm making this thread to ask someone with modding knowledge to please, please, please, replace these tree's model:

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With these:

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Reason: Even with a good system, Sunrays/SSAO OFF and Stivaii's textures there is a 30-40 fps loss wich doesn't happen near the trees of the second picture.
Misery is a hard mod and whenever the fps sucking trees are the battles become harder because for some reason when scoping/aiming near these trees the fps drops even more and aiming becomes unbearable.

So please if someone could replace the models or teach me how to do it I would be very grateful.