S34 to S46 12v battery 100% interchangeable for base model?

Sorry for what seems like a silly question to me, but I tried a few different searches and came away empty handed. My wife has started encountering no start / low battery issues on her 2007, so I am going to buy a new one. She has the smaller, S34 size battery and Costco only lists the S46 as an option to order. Toyota can order either for the same price, but I'm wondering if there are any actual component differences between the two, such as a different hold down bracket or if the fusible link/terminal assembly is different for the longer S46.

 

I just wanted to provide some conclusive guidance for anybody else in the future. The quick answer is 'no' they are not 100% "drop in" interchangeable for people who have the base model. The top bracket wasn't an issue at all, but rather the end of the base bracket. The bracket length is specifically for the S34, so you can't wedge the longer S46 in there.

My wife needs her car for Monday, and thankfully the bottom bracket end plate is just spot welded on. So rather than waiting to source a used bracket that fits an S46 I drilled out the spot welds and detached it (circled in red in the sample image). I also hit it with a quick shot of black primer to clean it up. There was plenty of room to tighten down the top bracket so the battery doesn't shift at all.

As for fitting the positive terminal/fusible link unit with the S46 battery, the top brace already has two adjustment holes, so I just pried out the Christmas tree fastener holding the unit to the top brace and put it in the second slot. I forgot to take a picture so I snagged one from another post on here. To the right of the circled "gap" word you can see the two perpendicular holes.

 

'No' in the sense that if you're looking online, some places only list the s46 battery as a direct replacement, which gives the impression that it's a drop-in fit for base models. If were not mechanically inclined or decided to just take it to Costco to have them replace it, they wouldn't be able to.

'Yes' in the sense that if you either a) do what I did to modify the bracket (which requires a drill and appropriate bits, at minimum), or b) know ahead of time to purchase a larger replacement base, then it will work. The intention of my follow-up was to communicate that for future searchers.