That images I post back in that topic are drawing with basic measures, is not more relevant ( but If I remember make by a user forum called JAK), today exist better information, like the manual or the French drawings, the only AFAIK available.
Are too one crude drawing in the manual of Russian version of this grip, the P-1M used in Yak-7, La5... and post WWII in early Mig's.
Bauer and Cheb2006 KG's versions - the best manufactured for now based on 3D drawings are based in these this drawings (manual and French).
Perhaps the best place for ask about right measures is in
Keypublishing forums where collectors hang on.
Some toughs:
Don't existe the right "KG grip, they manufactured by two different brands and sub-contractors, resulting in slight variations, so the only way to have the "right"one is get a original (difficult and expensive) and copy then (maybe 3D scanner).
For game controller purpose the know drawings are suffice (IMO).
Anyway M.Terluzzi Tail Boom KG-12A 1:1 resin copy is supposed cast from original, but has errors, like the support for B-2 Knopf.
http://www.hyperscale.com/2009/reviews/kits/tailboombf109stickbg_1.htmKG-12 or KG 13 are names used by different manufacturers for the same grip. The B version is due the added side button (B-2 Knopf) for drop bombs.
Good info in Cheeb2006 topics:
https://forum.il2sturmovik.com/topic/23860-kg-13-kbtt-another-one-look-replica/https://forum.il2sturmovik.ru/topic/4599-kg-13-ot-kbtt-eshyo-odin-vzglyad-na-sozdanie-repliki/Some pictures vanished in some image host "kidnapping".
I suggest you PM Captanblood in the Russian forum (use the login for English version), he seems have good info about.
.