After fighting the rusty nuts, I took out the sender unit from the Syncro.  The little plastic connector piece broke off, otherwise the whole unit is fine.  
Anyone would know how to fix it?  Is there a similar connector unit to replace it with?  Only one wire comes from the inside, the other is from the body.  
There maybe something I can use to replace that broken off plastic part of it.  It is way too expensive to buy a new one for such a small fault.
Zoltan