This is a rev of the servo? How much wider is the body?
If it's really close, I'm wondering if simply making up a sanding block (sandpaper wrapped around a block of wood) and taking down the case a little on each side would help. I'd be tempted to file the brackets as well (but then I'm familiar with metalworking). Possibly not something you want to propose as solutions.
Issue a warning for that particular servo?
Or, It looks like just a small space between the ears of the servo and the bracket. How about some small spacers?
It is a different new
model to replace the HS-475/HS-5475 servos.
While it is rated a few oz-in more than the HS-x475 servos it also appears they added some cost saving measures like no rubber boot where the wire leaves the body.
The significant dimention that changed is the depth below the mounting surface. It increased by 1.48mm.
You can't really sand
1.48mm off the bottom of the servo since that would put you through the plastic and probably start eating into PCB.
You can't add height to the mounting surface because you change the distance from the top of the servo horn to the bottom of the ASB-04 so your C-brackets and stuff would then be too narrow.