This will modify your IS-6 (Object 252) to look like the Defender (Object 252K)

INSTALLATION:

Simple method: Copy/Move the <vehicle name>.wotmod file from the archive (zip) to the World of Tanks/mods/x.x.x folder, where x.x.x is current game version
Better method: Create a folder in the World of Tanks/mods/x.x.x folder, where x.x.x is current game version, named vehicles. Then move the <vehicle name>.wotmod file from the archive (zip) into the that vehicles folder. This keeps things a little more organized.

IS-6 as Defender