are they custom jobs or otherwise? because from what i've researched they've labelled three different cabinets, the ta-6, ta-8, and ta-10.
the 20-u is supposed to be the same size as the ta-10, or 16 15/16 x 4 13/16 x 13 3/4, according to the attached file. the ta-6 is 17 3/4 x 5 1/2 x 13 3/4...