MiG-15/S-102 identification?

As most of you probably know, the S-102 was the Czechoslovak license-made MiG-15. Correspondingly, the Mig-15UTI was assimilated as CS-102 and the MiG-15bis was manufactured as S-103.

I’m interested how did these differ compared to the Soviet-made ones.
Is there any way to tell them apart from the outside? Are there any internal changes?

I’ve heard that MiG-15s had steel wireing (electrical systems), whereas the S-102s had copper wireing – don’t know how accurate this is.