Here below is a summary of what worked very well with all the nickel plated parts of my much beloved circa 1943-1948 model O42 chest. The various parts had relatively minor surface corrosion, none of it serious enough to merit the use of (aggressive) rust removal chemicals which tend to attack the plating.
1) Buildup of accumulated grime removed with Liberon furniture cleaner, a stiff detailing brush and a microfibre cloth.
2) All pieces Dremel tool brass brush polished (lightly at low speed!) and then hand-polished with Autosol metal polish followed by silver polish. The result of this was a pleasing shine with an element of patina and ‘story’.
3) All polished pieces were then coated in microcrystalline conservation wax and immediately buffed to a high shine. I use Renaissance Micro-Crystalline Wax Polish for this and many other purposes and can highly recommend it. It is an exceedingly high integrity barrier coating.