My 1970 Twenty Folder was missing the rear rack and chain guard. I adapted a full-sized Pletscher rack ($2 at the Curious Velo swap meet) to the smaller Twenty size by hacksawing the arms to length, then flattening the ends with a hammer and file and drilling new mounting holes. The chain guard ($3 at Curious Velo swap meet) is an aftermarket item, cut to fit with a pair of tin snips. It does the job and matches the chrome fenders nicely.

Replaced the broken plastic-faced 3 -speed trigger with a classic mid-1960s version from the junk box. Saddlebag is aftermarket NOS, and the B72 saddle came with the bike (lucked out on that one). Still on the lookout for some prebuilt 20" rims preferably with a Sturmey AW hub.

IMAG0684 by w1gfh, on Flickr
IMAG0685 by w1gfh, on Flickr
IMAG0686 by w1gfh, on Flickr
IMAG0687 by w1gfh, on Flickr
IMAG0689 by w1gfh, on Flickr