zenon11 wrote: Rather impossible, because and what can be argued there
I assure you that human imagination has no limits.
Maybe it is a coincidence that the synchro failure coincided with the replacement of the clutch, but I know from experience that if a problem occurs immediately after some intervention, then 95% of the problem is caused by this intervention.
A similar problem once caused me a professional mechanic in 307. He lost a small screw and did not want to look for him. After three days, the customer returned with the problem just 3. After searching, it turned out that the lost screw was lying on the cable bracket. Her removal solved the problem.
But this is just an example of a failure caused by unlimited imagination (or rather the lack of it) of a mechanic