ive done almost every modification on my car myself (in the middle of doing my dual exhaust i couldnt get the over axle pipe out so i gave in and took it to a muffler shop). how hard/necessary is it to install the t-lok and/or different gears? if i did go to different gears, which i think i will, which one would be better and again how hard to install? (could i do it myself or with the help of a friend?) thanks