HJ, I am happy to admit an error but there is no evidence presented that gives any indication that this pair of Evans are anything but W&R Screwgrips finished to No 1 special standard.
As mentioned there are two major screwgrip variations; one with a doll's head (per the Evans) and another with a straight extension that is stepped down for the "screw grip" grip to engage. The doll's head has the step at the back of it, too. None of these extensions are in any way hidden.
For more detailed information on screw-grips, (supported by photographs), see the following from these esteemed British gun experts:
Geoffrey Boothroyd, "Boothroyd on British Shotguns, chapter 'The Webley Screw Grip" p. 216-221. Photo shows the doll's head variant with barrels raised to show top extension." Also a screw-grip Evans sidelock.
Douglas Tate, "Birmingham Gunmakers," p 114 for technical explanation, p. 118 for photo of W&R No. 1 with doll's head extension clearly visible.
Ron Forsyth, "The Ubiquitous Screw Grip" a long feature article in Shooting Sportsman magazine with many pics of both variants, a patent drawing showing doll's head; moreover page from W&S 1922 catalog (1922, I think) clearly showing doll's head top extension on both screwgrip W&R sidelocks and screwgrip A&W boxlocks.
Last but not least our resident expert "Smallbore" -- Diggory Hadoke "Vintage Guns," p. 133 explaining bolting system and pic of straight, stepped extension variant.
A single author of this calibre could conceivably be wrong; it is most unlikely that all of them are!
