Here's a close up look at the great early production IBM Model F 122 single-piece key texture.
ANSI modified thanks to the great guide posted by fohat.digs.
Higher resolution photos are available to view/download here - the difference is much more noticeable in person and in these higher-res photos than in the attached files:
http://imgur.com/a/jdRSNThe F122 is part number 6110344. This keyboard is from June 1984, and these single piece keys have some of the best texture and dye sub quality I've seen. Probably long before the stencils started to wear out and before "multicolor" was used instead of the legends being a deep black color.
On some photos I placed two later-year Model M key caps directly on top of some of the home row keys for a more direct comparison of the key texture and quality.
The non-original keys (including the F and J keys with "nubs") are from a regular Model M. The num pad number keys are two piece and from a non-6110344 F122. One barrel was removed from the cursor area to better emulate the inverted T cursor keys as they are on the Model M.
The photos also show the paint texture of the top plastic piece. They are hard to tell from F122s with non-painted tops unless you see them close up, but look nice in person.
