grundig: Capacitor List to Swap?

Hello to all. Although I've owned my Gundig Console for a while now (I drew the tuner drawing you will find on the CS250 page) I've never given here a proper servicing. I am not experienced with vintage radios or their capacitors and I'm having difficulty identifying which caps should get swapped. 

My instinct tells me to replace all the caps that are cylindrical in nature and leave the rest untouched (except for C15 and that blue axial cap to the left). The schematics tell me that all of the cylindrical caps are non-polarized and that is why I am here...what caps should be used here? Any guidance is greatly appreciated...thank you.

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Maybe none.

I see it has locfit transistors so maybe even early 1970s.

Some electrolytics might be leaky (see idle current) or be dried out. Probably OK if the performance is OK. It's not like the issue of paper dielectric (waxies etc) or old US silver mica issues (v. rare in Europe) on valve/tube sets from 1921 to 1962 approx. Even those it was a minority of electrolytic (polaraised, + & -) caps that needed replaced.

There were indeed some makes and bad years even on modern gear for electrolitics. You can check ESR, leakage and capacitance with the cheap LCD panel mult-component testers, but only if there is a performance issue such as low gain, distortion or much higher than spec idle current.
 

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Thank you for the guidance! I decided to simply swap out just the caps that need attention...mainly the elctrolytics on the main PCB and amp. I also took to cleaning the pots and some contacts with cleaner and Deoxit.

Funnily, the bulbs that light up on the main display never worked...Looking over the schematics, I found that they are powered directly from the multi-pin connector and that its fed from the amp. It turned out that the contacts on the fuse were so corroded that it wasn't making any kind of contact to the fuse. A simple cleaning and everything is working 100%.

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Regarding the blue Philips electrolytics, those with grey or beige rubber at the positive lead are usually dried out now, while those with black rubber often still are in good condition unless they have been stressed with strong heat, overvoltage etc. An exception is the very smallest ones, about 3 mm (1/8") in diameter, those are unreliable even if they have black rubber.

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