DDK - Die Deutschen Klassiker

Does the box have an inspection window to view the pressure plate and clutch?

Clutch cable seems to be stretching or the pressure plate is wearing. Does the engine and transmission have to come out to make the determination?

First off, check your clutch cable, by removing if necessary. As the strands start to break, the cable stretches gradually.
Check around the rear bulkhead where the cable guide tube comes through, to make sure all the metal around it is sound and has not given way.
Also check that the scroll pin on the clutch pedal is tight, and the pedal is securely attached to the cross-shaft.
If all of these are OK, set the free play on the clutch cable and take a test run.
To check out the clutch itself is a full engine out job.
Cheers
JW

Thanks, car was up on the lift yesterday, and the clutch adjustment point didn't have a lock nut on it. I think its been that way for its life, and was never a problem. So a lock nut was put on, clutch adjusted but I am purchasing all the new cable bits.