My 27 EW duggie (still a project) has nickel plated parts all over it, and some have survived quite well
- it was poorly stored at some stage in its life.
I bought a nickel plating kit to do all the small fittings, but have yet to use it.
Others have had quite good results with these, you can leave the parts in and get a good heavy layer of nickel,
like the originals had.
Chrome didn't appear on most bikes until the early 30s, don't be tempted to go down that path ?
And yes, some bikes did have it in the very late 1920s, but you can count them on the fingers of one hand.
Its splashed all over the brochure when it did happen.
Douglas wouldn't be one of them (?).