Hi Gary,
I really like what you're doing here, and I can also really appreciate the issues you're running into! I'm doing a similar interior for my StuG IV late, also based on one of the DML kits.
Oddly enough, it was those dang radios that snared me too - They're just too freaking nice to hide away inside the model, but once I decided to show them off, one thing lead to another, and before I knew it, I was caught up in a full-blown fighting compartment interior job!
At about the same stage as you're in right now on your StuH (trying to stuff the ammo racks into their proper places) I discovered that the issues I was having were caused by the simplifications and compromises that DML had to make with the kit's superstructure. When DML designed the kit part, they obviously weren't thinking about adding an interior, so there are some missing details on the interior front wall.
However, the main problem that I ran into was that the kit parts are much too thick which reduces the available space inside the fighting compartment. The main place that this affected my build was in the ammo storage areas. The kit superstructure walls reduce the available space by 1.5 - 2 mm depending on where you're measuring. This meant that my ammo racks (which are based on the fixed prototype dimension of the shell diameters multiplied by the number of shells in each rack wouldn't fit!
What I had to do was thin down the interior thicknesses of the superstructure walls on either side of the opening for the gun. The outside interior walls also need thinning, but there's not much you can do there since that begins a ripple effect with the other interior details. But the inside walls next to the gun opening can be thinned down quite a bit.
If you do this, it might allow you enough room to move your ammo rack slightly forward reestablishing the visually proper spacing with the radios and other side sponson details.
Here's a picture of what I'm trying to describe. On the upper left is my StuG IV and on the upper right is the same area in your StuH. The areas in the red ovals are where the missing interior superstructure parts are needed, and the red arrows show the interior walls that need thinning to fit the ammo racks.
The bottom photos show the same areas in a couple or restored StuG III G's. Realizing of course that the ammo racks for the StuH and the Stug IV were different, you can still see how the available space the the front of the superstructure was used to store the ammo. (And for the StuG III / StuH how the driver's entry / exit clearance was reduced by the superstructure intermediate wall.)
Anyways, I really appreciate what you're doing here and just how hard it is to get all the correctly sized additional bits to fit into the reduced sized model kit superstructure.
However you decide to proceed, you have my complements!
HTH, and good luck! I'll be looking forward to seeing how this one all comes together.
), I detailed the radio outside and installed it afterwards. Only way it could likely work for me.
the top will be removable so to be able to see inside. 
I hear you on Battlefield 3. But, it's almost a clone of CoD: Black Ops. If you can, spring for MW3. The graphics are unparalelled.
im also unsure as to the wireing and routing of the headsets and where they plug into. all the photos i have leave me scratching my head a bit because they all seem different and alot of the details are a bit obscured. i could definately use more info and advise. 
ill have more pics later on. Thx Bob and everyone for looking.
