Adding new parts, got some questions!

Depending on the dealer

The Hurst could void your transmission warranty (syncros and related parts),
the T-loc and gears your rear axle warranty.
If your worried about your warranty don't mod till it expires.

the hurst should not void the warrenty, some dealerships actually put them in some of their upgrade packages. just keep in mind the hurst shifter for the v6 rattles. as far as the gears, if you are going to drive this car on the street for a manual 3.73, for an auto 4.10. the gears will void the warrenty on your rear end. same with the lsd. adjusting the computer for the gear change can void warrenty on the computer. not too mention if the dealer ever reflashes or updates your computer you will have problems. when you change out the gears and add limitted slip, you should always replace all the bearings to be safe. you also might think about getting an 8.8 rear from newtakeoff. you can get them with the gears of your choice and t-lock. they are a direct bolt-in and perform great.