Help with T-5xxx nomenclature

Hi all....I'm building a T-5xxx using Rossagraph and Kagero books as refernces.
My idea is to built a polish T-55 used by JNA troops in balkan war.
I've posted some photos of my work over armorama and we've had a debate about nomenclature.
What we've found intersting and one of the point of debate is the squared air filter hatch.
These squared hatch is a typical feature of T-54.
Oblung air filter hatch is the one of T-55.
On the references that I've used,the tank with squared hatch is called T-55.
My guess is that T-54 rebuilt can be called T-55 by Polish Army.
I post here cause I hope that someone can help me to get the right nomenclature.
At least I wish to know what I've built
I post some pics of my work.
Comments are welcome.
Regards
Ciro Riccio

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Russian Type snorkel still in wip
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