I have to think back to all of that stuff - I've been on the 4000 for 18 months now, but I had 16 years on 9006....
I believe you will use DIS-DEST to display the DSS and DDS keys that might be set up on that phone. Note that 9006 calls name/repdial keys "DDS" keys. DIS-DEST will also let you look at the forwarding assigned to the phone and etc....
DIS-KEPRO will let you look at the layout of the button tables.
DIS-KCSU and KASU will show you the line appearances on the phone and whether they are set to ring, and other preference settings. I forget which is which, but one shows the line appearances and the other one shows various setings about the phone, like which key is the prime line, etc....
To make changes you would do CHA-DEST, CHA-KEPRO, etc... I recommend you always display everything before you change it. That way if you screw it up you will know how it was before you started