You really need to install those brackets, they will prevent your traction bars from digging into the ground and I think they also help with braking.
I had them on my last mustang and the brackets hit on everything it seems like, especially speed bumps.
------------------
James Cox
nochevy@hotmail.com
1991 Mustang LX
Best 1/8 time on motor 7.686 @90.20mph