Thank you very much Lance, Frank, Juan and Gregory. Your comments are highly appreciated! Frank, there's luckily no competition, as I won't ever reach your level of microsoldering e. g.!
Meanwhile I made some sear belts out of Tamiya tape and some thin thread. It still needs some detail painting and some highlighting of course

On the left fuselage side I scratchbuilt a magneto switch and an oil pulsator. Additionally I tried to improve the fuel gauge by adding some clear plastic.

On the right -- OR starboard-- side I added a tachometer. I ised some evergreen plastic, some brass rod, a HGW bezel and an airscale decal for that.

So far from my side. I am still thinking about how to add the internal rigging that connects left and right side of the fuselage. Here building up an independet interior structure that is sandwiched between the fuselage halves would have been a better way...
Best regards
Borsos