Good starting point, I think you can make it better, here are some remarks:
-you should add what the vga port on the Tool motherboard is for, and the svideo port too while you're at it.
-I don't think tips 2 and 6 are needed as they aren't Tool specific.
-for tip 14, be more precise on which hdd are you calling the first one
-tip 15, you should write down the back dipswitch settings here to make it simpler, or specify in which .pdf document from the official sdk the info can be found.
-the tip about running games in OPL should be after the section where you load OPL on the Tool, also you should write the model numbers for the PCMCIA ethernet/hdd interface cards and external hdds.
You wrote that the T10kH have an extra network card, do you have any proof of that?
Replacing the cmos battery on the SBC is probably worth mentioning before changing BIOS settings.
I don't remember if the telnet daemon isrunning by default on the Tool.
I think you're confusing using the dsnet clientd from a networked computer with connecting through telnet to the Tool...
I'd argue that resetting the root password is easier by booting linux in single user mode from the Lilo prompt than logging into the diagnostic checks user account and exiting the running diag checks to run the passwd command.
I think the network settings can be changed from the web admin interface.
And if you start playing with vi, you should add a short list of command to correct typing errors, or atleast exiting without saving the file being edited.
Also, a tip on what to do if the network config info screen doesn't display the network settings on the PS2 AV out, some people had this problem.
And from your last post, what are you using to restore a hdd dump to another hdd (or CF card), creating the dump in the first place isn't any harder, and chances are the software you used can do both.