I had a been using a Group 24 Battery, purchased in 2014, and do not remember an issue even though the battery was slightly narrower.  If you’re using the stock hold down support, you could sneak a ¼” shim (wood?) in the upper bracket on each side and it would not be that noticeable (IMO), or cut, shorten and re-weld the top support. 
(Note that I had switched to a trunk mounted Optima battery in 2020)

It keeps sliding off one side or the other. The older battery's were the thicker rubber cases that were 7" at the top back then. For yrs. I had a metal frame that made up the slack & covered it with them fake looking Autolite covers. They warp and crack from the heat and the metal rots. So anyway I tried heating up the plastic hold down and bending together more and is why there is a new one on the way. I just like trying to keep factory looking.
I will check to see what other batteries might work better. Can't go by the size charts because there measurement might be at the bottom where the hold is.

11 Years is great.  My last platinum battery only lasted 3 years.  The max I've been getting lately is 5 years for my drivers.  

I don't expect any new battery's to last long. 11yrs ago we could get one that had 6 to 8 yr. warranty which is what this one was. Today only 3 yrs.for the best. No virgin lead mining, just recycle stuff. Don't hear good things about optima for what they cost, so I stay away from them.