Check out this Kalamazoo Mandocello (http://www.rumbleseatmusic.com/pix/30sKalamazooKK-31SB.jpg). Doesn't look like it's a conversion does it? Anyone know anything more about these, it's the first one I have seen. I'd also be interested to hear how it sounds.
I bet it sounds like a Gibson L-50 with 8 strings and minus a truss rod. http://www.mandolincafe.net/iB_html/non-cgi/emoticons/smile.gif
I don't think it is a conversion.
According to Mr. Gruhn the KK-21 Mandocello (same style as the KG-31 guitar)was available from 1936 to 1938. The KK-32 (same style as the KG-32 guitar) mandocello was also built with a total of 2 shipped in 1940.
L-50 size, 16" wide, arched (not carved.... think pressed) spruce top, mahogany back, bound top and back, brown pickguard, trapeze tailpiece, unbound rosewood fingerboard, dot inlay, sunburst finish.