These are just wery little things, but I thought Id mention them anyway... Dont take any stress from this!
The T-26E vickers should have a Suomi BMG, that is the English vickers that got it's crew increased to 4 and the 37mm bofors replaced whit the soviet 45mm gun (well the gun change actualy happened after winterwar). The no. 4 crew man was added already when those vickers tanks came to Finland in 1938-1939.
They were originaly meant to have a custom engine (and shipped to Bulgaria IIRC), that changed the turret to be offset to the right to give room for bigger side mounted engine. But since they were refitted whit the standard size engine and sold to Finland instead, Finns used the extra space on the left hull on these modified Vickers tank hulls to add that fourth guy and a Suomi BMG as hes arnament on a fixed mount of domestic design.
T-26 m 1939 should have a DT bmg not suomi BMG, that is the OT-133 modified to be gun tank and fourth crew member added whit a fixed DT BMG mount. Same thing basicaly as whit the Vickers tank, but for a different reason. The OT-133 (and OT-130) had it's turret offset to the right to give room for flame fuel tanks on the left hull. Finns removed those and put a fourth crew man there. Also the flamer was removed and replaced whit a DT cmg and 45mm gun in the turret converting these flame tanks into gun tanks. Whit better availability of captured stuff now they added the DT bmg instead of the Suomi SMG as hull arnament.
These modified T-26 and vickers tanks are unique for the Finns (well ofcourse not all captured T-26 tanks were modified this way in finnish use just the OT-flamethrower ones). Normal Soviet T-26 had 3 man crew and no bmg. There are pictures of finnish modified 4 man OT-130 and OT-133 below:
OT-130 FINN MOD:
http://rkkaww2.armchairgeneral.com/g...6/2/T_26_1.jpg
OT-133 FINN MOD:
http://rkkaww2.armchairgeneral.com/g...3/T_26con1.jpg
And here is a normal Soviet T-26 for referance so you see the horn and also the headlight on the front hull, but no BMG mount. This particular one also has additional lights on the turret for night fighting use.
http://rkkaww2.armchairgeneral.com/g...26M35RT_3b.jpg
Btw. Only difference between the OT-130 and OT-133 was that the 133 had a sloped turret.
Wow quite a long text for simple thing really, hope you can make sence of it.
SPWW2 fin oob has these pretty much correct so you can look there for better referance if you like.