3DS Updates on SD

So recently I've noticed that when I power on my 3DS (original model) that it prompts me to install firmware updates. This only happens when I power it on with the SD card inserted, so I assume the update it downloaded at some point is stored somewhere on the card. At some point I would like to pick up a flash kit for it so I've been holding off on installing any updates (it's currently on 3.0.0-6U)

So my question is, does anyone happen to know where exactly on the SD the 3DS stores downloaded updates so I can delete it and stop the update nag on powerup? Or is there some reason I should just let the update install? The only thing I use my 3DS for is playing the handful of games I own, I don't normally use it online at all.

I wouldn't let it install no and no it's not stored on SD though it may use the SD card while installing, I know the SD card has software settings though and it may use those as a way of telling if an update is needed

At the moment there are only like 3 kits now that work on the latest 3DS update

1 of those kits you actually need to email the official site to get the update (I'm guessing to prevent theres from being blocked again) so on the outside only 2 flash kits work on the new updated 3DS firmware

Not got me 3DS to hand but I'm sure you can turn off updates, though you will get warning for the eShop every time and some software may need an update to keep working, some games have even come with there own firmware update (Mario 3D Land or Mario Kart 3DS was one of those)