Identifying small parts|Winchester Rifles|Forum|Winchester Collector

What is the best way to identify a large amount of small gun parts many of which are Winchester? Looking at old catalogs and part lists has only gotten us so far. Are there any lists which show parts in 3 dimensions and/or give measurements? The man tore down guns and put the parts in buckets,cans,kegs,cigar boxes and none had any identifying info. The big parts are easy but the internals is proving a nightmare for us.He also mixed up pistol,shotgun rifle parts in the same container. Everything is starting to look alike.