I have a GSA-4166b drive and I just flashed it to this from being a GWA version and now it doesn't write. It errors every time.
How did you get past the model mismatch problem? I am trying to get mine back to the GWA and flash it.. but I can't get past the model mismatch issue.
Also, would you recommend me trying to further bury myself in this stuff by doing what you did and flashing it to be the HP model you did?