I’ve been combining my sculpts for years. As each new game comes out I take notes on the contents, particularly on the appearance and colour of the sculpts, then I put the sculpts into Flambeau Zerust plastic storage trays (tackle boxes with movable dividers). The trays are slotted into low, wide, stackable wooden storage shelves (the kind you buy flat and assemble with a screwdriver). The trays are arranged by country. The US, Britain, Russia, Germany and Japan currently have four trays each, due to the large number of sculpts each country has. Each of those five sets of four trays starts with a large compartment devoted to the main infantry pieces for the country in question, followed by smaller compartments for variant-colour infantry (such as the dark green US marines from the original Pacific game) which I use represent elite or special units. After the infantry, there are tray sections for the various equipment types (land units first, then air units, then sea units), subdivided by specific types (tanks, field artillery, anti-aircraft artilley, etc.) in the main colour (or shade) for that particular nation. Then comes a section for infantry units whose shade is problematic – different from the main shade, but difficult to distinguish from it under most lighting conditions. (Most of the pieces with this problem are the American troops, which have been produced in about ten different shades of green, but fortunately it’s not a problem to quarantine the problematic ones because I have such a large number of correct-shade ones.) The final tray sections are devoted to equipment pieces which either have ambiguous-shade problems, or which are radically different in shade or colour (like the cherry-red Japanese equipment units from the original Pacific game).
Italy, ANZAC, China and France are less complicated (because their pieces have never been produced in multiple colours or shades) and require fewer trays (because they’ve been in fewer games, and thus I own fewer of them). The order of the pieces in the trays is the same as for the Big Five: infantry first, then land and air and sea equipment. Italy’s pieces occupy two trays, in part because they include the German-design and Japanese-design pieces with which Italy was first provided, plus the Italian-specific designs from Europe 1940 2nd edition. Due to the many ANZAC pieces I own, ANZAC would in principle have two trays too – but what I’ve done instead is designate the Pacific 1940 2nd edition’s butternut-grey units as ANZAC ones (in their own single tray) and the Pacific 1940 1st edition’s butternut-grey units as Canadian ones (in their own single tray). China is in one tray, with the Chinese infantry supplied by Anniversary and by Pacific 1940. China has no official equiment, so I use one-half of the lime-green British equipment from Revised to fill that gap. (More on the other half in a moment.) France is in one tray, which represents both the Third Republic and the Vichy regime.
The project on which I’m currently working is to integrate the new pieces from A&A 1914 into my collection. I’ve taken the blue 1914 French pieces and put them into half a tray, where they represent the Free French forces. (I haven’t decided yet what to put in the other half of the tray.) I’ve taken the pale green 1914 British pieces and put them into half a tray, where they represent South Africa. The other half of that tray holds the second half of the lime-green British equipment from Revised, plus the lime-green British infantry units from the same game, to represent India (which technically is just a British imperial colony rather a Commonwealth Dominion, but which is an autonomous regional economy in the Global 1940 rules). That leaves six 1914 sculpts sets whose use I still have to determine (which will be my project for next weekend), plus the generic equipment sculpts from the Milton Bradley edition.
I also have a single tray in which I put the generic-shape (and generic-colour) anti-aircraft artillery units and industrial complexes from the earlier A&A games, plus special extras from various other games I own: atomic bombs, nuclear mushroom clouds, city markers and so forth.