While looking over a friend's early mustang drag car today I noticed his 9" tubes are stepped down out towards the axle flange. We ordered up a Chassis Engineering back brace to fix it up while the car is down for winter. It's going from flange to flange around the coil over brackets, etc.

Do you guys weld the entire perimeter of the back brace or? [/quote]

Yes.. weld the entire perimeter and run the brace
to the ENDS.. I actually go up onto the bearing ends
but make sure your bolts clear the brace