Here's the working player model. Just unzip it to your Quake III Arena\baseq3 folder and you should have a new character in the game.
README
Quake 3 Player Model - Bugsy version 1.0
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Copyright 2004, Kari Brown (kb.info@luukku.com)
All rights reserved.
Model Path: /baseq3/bugsy.pk3
Number of Polygons: 1098
Number of Skins: 1
VWep Support: No
Sounds Included: Yes
CTF Skins Included: No
Description
Six limb bug -type character for Quake3.