Please +rep me! More will come!
First record yourself putting your car on rally and then remove it. Then, search for your username using the magnifier glass with the 3 dots. Keep clicking it until you see a packet like this:
53.4000.732.1.28185.btn19.(your profile code).732.(Your username)..
now you need to edit the packet. Change the 53.4000 to 53.4003 and btn19, delete it. Now it should look like this:
53.4003.732.1.28185.(your profile code).732.(your username)....
Now you change your profile code to the person you want to boot's profile. Change the username to something random so you don't get banned. Click Ok and play continuously for 100 milliseconds. There you're done. Hope it helps. :]