I would recommend HTmodels Petlyakov Pe-2 Pe-3 booklet. It's got some good interior pics in it. However after an internet search I couldn't locate a copy for sale, but I did find this
HTmodels special Pe-2 Pe-3 which may help you locate one(I hope). I have this and the Hpm kit half completed so I have a pretty good idea what you are up agianst.
Most of the pics are of "restored" planes with some "interesting" colours, some can be found on the 'net , such as
If you will notice in the first pic what appears to be a light blue/grey basic interior colour and many of the components in green. If you follow this link
Mig 3 VVS colour chart and scroll to near the bottom you will find "Interior colors" and at the top of the list is "A-14/A-14f steel grey" , this would be the grey color, how ever, as dark as it would appear, Model Master neutral grey comes recommended as a reasonable match. Now If you scroll down to the bottom you will find "Primers". At the bottom of that list is "ALG-1 Zinc-chrome yellowish" , This is basically zinc chromate. Bellow that you will find "ALG 5" which is a mix of "ALG 1" and "A-14" , very much along the same lines as US interior green, this would most likey be the green, which is not standardized colour.
Here are some pics of a Tu-2 which clearly show those colours.
and just to show this was most likely not limited to planes, here is a pick of the Transmission compartment of a T-34 pulled out of a bog
In the HT book, there are several interior pictures of what looks to be an unrestored plane with an entirely green interior. The rear section looks to be more of a bronze green while the forward section is more like US interior green and there are bits and pieces of various shades in between. However these are pictures and not the best way to judge what the colour of something was. Going with that and these bits and pieces allegedly belonging to a Pe-2,
I would suggest that the interior of war time produced Pe-2's were most likely left in a primer green similar to US interior green/bronze green, of which some components may or may not have been left unpainted.
Good luck with your build, I look forward to seeing it :drinks