So off and on I have been researching the Soviet version of the B-25D or known to the Soviets as the B-25DP. I did find some things interesting as they where equipped with the NKPB-7 bomb sight of which I am still looking for pictures.
Interesting enough from the book Lend-Lease and Soviet Aviation in the Second World War by Vladimir Kotelnikov they found they criticized the lower turret as well due to jamming when extended abruptly and limited field of view and replaced these with a pair of machine guns in the side mounts.
So far have not found any pictures of this but it is interesting. They also thought that the crew was too large and moved the equipment for the navigation to the nose of the aircraft with the bombardier doubling as navigator. They also did multiple changes with fuel tanks in the bomb bay. So far on all of the above changes I have not found any pictures but still am looking. What makes this even harder is that damaged US B-25's that landed in Russia where repaired and in-turned in Russia that where modified by US squadrons and used by the Soviets.
Hi Paul,
the Soviets called
B-25DP (B-25ДП) the D-models from
the two latest B-25D blocks: -30 and -35 only:
Those "hybrids" had the belly turret already removed and the side guns (the non-staggered) and the single tail gun factory installed. Check
this article in Russian. It's about the tests of a
B-25DP in the USSR. I believe there is a way to Google-translate this page or maybe there is an English version of it already.
On one of the photos you can see the bomb sight - I believe this is the Soviet model you mention above, since no Norden-bomb sights were given to the Russians. It could be the D-8 bomb sight though (this was the one installed on B-25 as per Russian sources)
Kotelnikov wrote a single book(let) about the B-25 in the USSR (I have a hard copy), but only a couple of pages are about the Soviet use. Print is awful, I think there might be a pdf-copy on the net.
You can find some interesting photos of B-25s in the USSR and some of the Soviet modifications (e.g. bombs) here:
в центре - к-н Мойсеев На заднем плане один из последних Ер-2 полка слева инженер по вооружению Пивоваров с-на Стрыжак в центре к-н Дремин
zaika70.livejournal.com
All a/cs are early models (C, D) with belly turrets. On one of them (after resizing, zooming in and out) there might be a side gun visible, coming out of one of the observations windows behind the wing - check this:
If this is what we think, it will be the first time ever I see a modification like this.

BTW for many years I was looking for a photo of a Soviet B-25G; AFAIK only 4 have been delivered, all of which went to the Navy as transports.
At the end I found one (don't remember where, possibly from a Russian site) and here it is:
Maybe there is a better one somewhere? Who knows....
Cheers!