I have a Pelican 1200 and it is perfect for my mirrorless camera, but my D3400 won't fit oriented like in your image. I have to remove the lens and put on a body cap then lay it flat. Then it just barely fits. I originally bought it for a bridge camera, for which it was perfect. I've been considering buying a larger case for the DSLR.>>3614898
Check out, "Pelican Pick-n-Pluck Foam," on Amazon,https://www.amazon.com/stores/page/CAB18B3A-D0F5-4A82-8978-69E92A66B655
The main foam brick is divided up into little foam columns. You pick out only the ones you want to remove in order to perfectly fit your gear's shape. Try to lay the gear on top and orient everything just perfect before you pick out the foam.
You should also replace the foam once every 10-15 years. It starts to get harder and break down into dust around that time, if it has been kept out of heat for the most part.