I had a problem with the holes in my chassis ben drilled too close together for the servo.. so took a few mm off the servo mounts and now it's fine..
Weird thing is my friend who is running the shame chassis (itf) and same servo (S9551) has the servo mounted in the same way as me just his servo has a bigger gap between the bulkhead and the front of the servo... Weird cars...
Easy to drive and easy to setup though which as a plus.