The "port 960, master slave a0" error that you are getting woul seem to suggest that your drive has been dectected correctly.
Name NVIDIA nForce4 Serial ATA RAID Controller
Manufacturer NVIDIA Corporation
PNP Device ID PCI\VEN_10DE&DEV_0055&SUBSYS_71001462&REV_F3\3&2411E6FE&0&40
I/O Port 0x000009E0-0x000009E7
I/O Port 0x00000BE0-0x00000BE3
I/O Port 0x00000960-0x00000967
I/O Port 0x00000B60-0x00000B63
I/O Port 0x0000F100-0x0000F10F
Are you sure that Raid has been disabled in your bios, or perhaps set to IDE mode ?
Also in Bios you may need to set sata bootrom to off. ? (I have no practical experience with an nforce board)
other than that all I can realy suggest is that you try different combinations of when to connect / power up the dvd rom, as there does not seem to be a surefire method that woorks for everyone.
Some people need to have the 360 booted but not connected to the pc untill they see the dos prompt.
some people connect the 360 to the pc, but do not power it up untill the dos prompt.
I realy do think that there is a little trial and error involved in this step, but as your drive has been dected, you should be able to dump your firmware with a bit af fiddeling with boot sequence etc.
I see that you have also read Rampantscot's thread on "mtkflash hangs with flashing cursor." The origional article that inspired that idea "recovering from a bad flash" (found at the bottom of GEEBEE's v1.5 tutorial on flashing/extracting etc, did say that you mat have to try the fix (type the mtkflash command then power on the 360 then hit enter) may need to be repeated a few times before it works.
I am sorry that I am unable to be more help, but I realy do think that you are now at a stage where you just need to experiment with when to connect / power up your 360. And of course tripple check you various bios settings.