DaveF,
There is a schematic for the Grunow model 1191/1191B chassis 11G at
http://techpreservation.dyndns.org/schematics/manufacturer.htm
The file is in DJVU format so you will need the DJVU browser dropin or the standalone program if you do not already have it. It is available at the above link. The schematic has the values of the parts as well as the part numbers.
Radiodoc