325 and M3 Rad fan differences ?

[BMG]

I need a replacement for my M3. Factory part is NLA, which is a shame because I'd like to rebuild to stock condition and the fact I used it at the track and didn't need an upgrade.
Looking at the ETK , this was M3 and 320is only. Looking at other E30s , the 325's and others use an identical looking fan under a different part number. So does anyone know the difference ?
The M3 part number is 64541381633

This is one available and for a 325i with the part number 64541376973
https://www.ecstuning.com/b-genuine-...y/64541376973/

Thanks