How to determine version of Thorens TD-160

I recently picked up a Thorens TD-160 turntable and I notice from the blue book that there were several variations of this table. How does one determine which variation they have? This table is just marked TD-160 on the Plinth. Upon removing the platter, there is a plate marked Type: TD-160 and what appears to be a serial number that is marked: B No. (this marked on the plate) with stamped number of: 184162 Any help with history of this deck (when made / price when new / how well thought of in relation to other Thorens tables / etc.) would be appreciated. Thanks!
Whyland, take a look at these web sites:

Tons of information and lots of interesting reading.