Mod Request: Chally 2 ATDU Barrel Change

[ItsTheGhost87 9]

a thing that's always bothered me about the Tier 10 Challenger 2 ATDU is the ingame change from the 120mm to a 140mm despite there never having been one ever mounted nor tested on a Challenger 2; since i am VERY unfamiliar with how to actually change the barrel model, i was wondering if anyone here could change the ATDU's barrel to the one used T9 Challenger 2 (or give a guide on how to do it myself) since it's not only more accurate to irl but imo looks WAY better
linked image below comparing it ingame to real life

Edited September 3 by ItsTheGhost87
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