To begin with ix 1.5 - 1.61 was not really spoofed at all. There is a difference with Lite-On from the other drive.
In Hitachi, Samsung and Benq the Inquiry data and Identify is stored as plain data somewhere in the flash.
There are a few differences in the way the data is stored. For example, in Benq, the data is repeated in all 4 banks. In Sammy and Hitachi the Identify data is stored as it is returned in the reverse format, but in benq it is readable. These idiosyncrasies all present issues, but nothing that can't be overcome.
With lite-on 2 issues presented themselves.
Firstly, the lite-on encryption algo was not available to team JF
Secondly, Inquiry data and the Identify data is not stored "as is" per say. The data returned has to be built up, firstly the the Inquiry/Identify data is read from the encrypted area of flash and THEN the drive barcode is superimposed over it, and for Inquiry the H/W rev is also inserted.
This made "safe" or correct cross spoofing pretty much impossible BECAUSE the area where the barcode goes in Identify and Inquiry is now "Common" data. BUT Benq, Bammy and Hitachi have different data in these regions. So if you got the Inquiry correct the Identify would be wrong.
So, for ix 1.5 - 1.61, iXtreme set aside and area at 0x13E00. If the Inquiry or Identify routines could see that this area was modified it would return this data instead. Team JF were given the various Indentify and Inquiry strings pre-encrypted and are written to this area based on the spoof required.
This routine IS considered to be NOT "Lite-Touch" material and was dropped.... so no more cross spoofing in LT.....