Hello all... As you probably can tell I'm new to the site and I'm ISO some info for safes. I'm looking for a low cost/fire rated safe. I've been really trying find a 16 gun safe in a convertible layout but haven't had much luck. The best I've seen was the stack on elite 16 but they have been hit and miss on the interior layout. Some are convertible and some are completely open with one top shelf. My big question is it possible to just get the open layout and add my own center divider and shelves to the one side? If so how are people mounting the lumber inside? Will screws hold in the material inside of the safes or do you need to use drywall anchors first and then tap into those? I want to make it look as factory as possible so I'll be adding carpet to the plywood or MDF to the additions so it doesn't look Mickey Mouse. Please if anyone could provide any info it would be great. Also FYI I know I could jump up to a 24 if no issues however I have very limited space where the safe is going and 24 is out of the question.
Thanks
Mike

You may want to look for a safe that has mounting tracks on the sides.  The standard configuration is two tracks on one side, then two on the other.

Many years ago I bought a safe without an interior, then made my own to save some money.  It was easy to do.

I used plywood, shelf type L brackets on the inner side, then those snap in shelf holders on the tracks.

I made it in an I shape, with a bottom foot, a top shelf, a center divider/support piece, and then gear shelves on one side, and long gun space on the other.

I bought a carpet rememnat from a carpet store for a few bucks, and glued in it.

Be advised that the number of guns you can get into a safe is pretty optimistic, and is based on them all being slim rilfes or shotguns.  If you have anything with some height such as an AR, or even a rifle with a big scope, you won't get as many in as listed.

That's what I'm looking to do. I only need enough room for 2 ARs, shotgun, and. .22 LR then have shelves on the other side. The 14 gun safes don't give me enough shelf space and can't find a good 16. Glad to hear it can be easily done.

The other thing you can do is use a rifle rod kit.
Take out all the cutouts and use a shelf to attach the velcro material to the bottom.
You can squeeze more guns in and move things around.