Question: Baseband version: **I9020XXKF1**

Current software build number is **GRK39F** on Android 2.3.6

I seem to have a pretty much unrecognised baseband version of the Nexus S. I brought mine carrier-free in the UK. 

There are a bunch of updates listed in this thread on XDA: <http://forum.xda-developers.com/showthread.php?t=1063664>

But there are 2 versions beginning with **I9020**, but they have extra letters on the end (no X like I do) : I9020A and I9020.

None of them match up perfectly, what update do I need/any dangers of using the wrong one?

Answer: 
My baseband is ever so slightly different from yours: it is I9020XXKI1 (I think; it's hard to read). I upgraded by following the steps at <http://www.androidcentral.com/how-manually-update-your-gsm-nexus-s-ice-cream-sandwich>; I am pretty sure that you can't go wrong doing the same. At worst, your phone will refuse to install the thing.
The correct build was [here](http://android.clients.google.com/packages/ota/google_crespo/VQ8PQk_V.zip). It's listed in incremental updates 2.3.6 - 4.0.3.