Common spot on 113 linkage is the shifting fork on the splined shaft gets loose at the clamping bolt.
If all other link bushings are OK , look right there first.

http://213.239.220.84/bin/dbframes.phtml?mid=IN02

A picture will help in locating
Go to this great 113 site and open the tranny link insert , then look at item
# 26 ..that is the fork that can loosen and cause you a problem like you mention.