Beolit 1503 radio diagram mismatch

I am restoring an old (circa 1970 vintage) portable Beolit 1503 radio. I found a circuit diagram inside in a small envelope. The problem is that the diagram does not match the printed circuit board layout shown on the back of the diagram page which also differs from the actual component layout. The component numbers (in red circles) also do not all match those on the diagram. Another discrepancy for example is that a given capacitor is given as 2,2microfarad whereas the actual component on the pc board reads 22microfarad. 
I have also downloaded the service manual for this radio showing both the foil and component side pcb layouts. These are similar to my radio's physical pcb but differs in a number of respects for example some components shown are not found on the radio's pcb. 
The pcb number also does not match the pcb number on the diagram found in the radio. 
Could this possibly be because of later modifications and if so, how can I get hold of these changes?