Hi, I scaned for you something, hope, it will help you - please, check your PM inbox.
As for colours: All internal surface left in NMF except cockpit in RLM66 and front wheel bay RLM02 or RLM76 because later in war was made of stell(source of info MBI and JaPo), and stell was always treated with some colour, usually primer RLM02, RLM66 or RLM76. Main landing wheels bay - NMF with some rows of rivets and 1st wing rib treated with brush painted RLM02. You wiil see on scans what I mean. Gun/camera covers are in RLM02. Gun/camera bay can be in NMF or in RLM02 - photos of both version exist.
If you would like build "white 3" you will need rework bulges over cameras. This particular a/c have different bulges - short version. "This rare version did not overlap onto the front section of the nose and is an unmistakable sign of non-standard solution, leading to our belief that it was converted to reconnaissance model at an experimental workshop possibly at Oranienburg airfield or at 3./Versuchverband des O.K.L" via JaPo - Messerschmitt Me 262 production & Arado Ar 234's final operations David E. Brown, Tomáš Poruba, Jan Vladař, 2012, p.11.
I dont know if you have this in your set, but a camera window was set into reinforced plate attached to the nose cladding. The plate also covered spent cartridge holes of the MK108 guns. Check shape/position on enclosed scans.