Have a look at step "6" of the Panzer IV D/E instructions.
Except for part C09. there can be other locations for the parts to fit.
Oh, and some of that stuff fron the D/E kit should fit onto the F/F2/G/H kit, but depends if you use the schurzen.
Pretty much, you can put it where it can fit and makes sense. There was no rule to storage. Just be reasonable with it and it should look and work fine.
[edit]
I forgot to mention. Sometimes it is a good idea to take a look at combat photos (from books) and combat footage (from documentaries) to see how crews actually put stuff on their tank.