Perhaps with a separate Main Menu item or when you go into the unit information, a sub menu in there. I think the first would work as you are looking at a name search split by unit or unit and then details of the officer as in the unit information now, clear??
I am thinking how I, as a user, would like to find this information. As in the unit information now and the name search, it is simple, which is always best. Perhaps the name search could specify a sub directory once you have searched and the person is an officer, flagged with a separate link to the files?
Just thinking, I was talking to Pete last week and like you, I have loads of photos of monuments and grave stones and have started to index them and asked if the forum could use them, or more likely how, so a way of uploading the file or photos linked to the name would be good.
Your reply does highlight the issue that this information would be better if it linked to the regimental structure that already exists in the main part of the site. I had a separate conversation recently with someone asking how all the information, pictures and forum posts on a unit could be amalgamated in one place. There is no easy answer to that short of opening up the site to a wider range of authors which I would certainly consider doing.
Alternatively, I could create sub areas of the forum for each unit and then provide links between the main site information for that unit and the forum area (and vice versa). That might work better. In that way, anyone could post information relevant to the unit in the forum. We have started to go down this route a little with the areas for the Cape Police and ILH which provide a wide range of information.
Officers casualties would just be another type of information that would be posted under the unit name.