Draw storage

Ok I have a 3rd row on 2023 SR5 premium and almost all draw systems I have seen says doesn't fit 4runner with 3rd row seats. Which I do not understand as it lays flat. I have no intention of using the third row never really wanted it in the first place can the 3rd row be removed and used for extra storage?. And I don't want anything too tall but I don't want a 2-in drawer system either I thought the happy medium would be a 5 to 6 in tall draw system just in the back for now I would also like to be able to put in a mattress with the second row folded flat option. Any info ideas recommendations I would greatly appreciate I don't mind DIY or Professional installation.

 

I came across this when contemplating the same thing;

https://www.youtube.com/watch?v=JKgGo_HUBeA

 

Yeah I saw that just trying to see if other options out there. Thanks