Goal is to delete an unwanted ability added by a mod. In this case I don't want a perma 5 pts Night Eye.
I've opened my save with Enchanted Editor and I think I've found the record I need under Player Spell Data. Problem is I don't know what to cut with the other subrecords. I noticed they go in clusters something like

NAME
SPDT This has the spell ID that tells me I'm in the right spot.
NPDT
NAM0
XNAM

So what do I slice? Everything from NAME down?

Edit: And is there a better tool to do this? I remember reading somewhere that EE can be buggy and make unwanted changes.

Delete all sub records attached to the branch petrtaining to the ability you want to delete.

Make a copy of your save before you edit it with the enchanted editor so if you do make a mistake then you won't lose anythinng.

it may work, I am not certain it will last through multiple reloads, but worth the effort as it is simple to do:
- take note of the spell id (e.g. yourSpell ID)
- start Morrowind, load a game, go on 3rdperson view, open the game console, click player (you should see PlayerSaveGame on console window header)
in the game console, type (pressing enter key to confirm a command line)
RemoveSpell "yourSpell ID"
RemoveSpellEffects "yourSpell ID"

Using the EE method I deleted all subrecords from Name down to just before the next Name entry. However MW crashes when trying to load the save. Either I'm doing something wrong or its not possible with EE.

abot's method seems to have worked including after reloading the subsequent save.

So it looks like mission accomplished although if anyone has successfully done this with EE I'd still be interested in knowing how.

Many thanks.