T-34 interior metal texture

[LooseSeal]

Hey guys, I'm working on a Trumpeter 1/16 T-34/85, wondering about something and hoping any T-34 experts might know!

 

Would the interior of the tank be a smooth finish or more of a rough cast? Ie: something I can replicate by stippling Mr Surfacer. Reference photos are either severely rusted and in bad condition, or just inconsistent or unclear. The front glacis interior does seem to have a texture to it, but the side walls not so much.

 

If anyone can offer greater clarity, that would be appreciated!!