I think the wear point in the transfer case is the splined joint between the transmission output shaft and the input gear to the transfer case. Shifting between drive and reverse when stopped can produce a noticeable clunk as the backlash in the joint reverses. The Australian McNamara input gear has been the relatively cheap fix as the gear is wider than stock, it mates with an unworn part of the splined shaft.
'03 KTM 450EXC
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