I've searched everywhere for answers, but can't seem to find any useful information on this subject. Is there a way to change the player character's size in the GECK? I know how to manipulate the size of all NPCs in the game, but I can't see my character's data. What do I have to do exactly?

You could do a script that runs at gamestart and uses the http://geck.gamesas.com/index.php/SetScale function to change the PC's size. Just don't go about roughly 1.2ish or they wont be able to walk through many doorways.

In the object tree, under NPC, search 'player'.

There are two entries, one 'player' and one 'playerfemale'. You must change the height attribute for BOTH of these two entries or the game won't register the change in-game. Or at least, it didn't work to only change the playerfemale for my female chr. Only when I altered both did she become shorter or taller in the game...I'm assuming it works in reverse re:male player-character as well.

Will that work for custom races? My character is a Glow race from the Mikoto Beauty mod and I don't see those races listed in the GECK.

Edit: Nevermind, it worked. Thank you so much for the help.