Prior to 1972, the mahogany F-30 body shape was similar to a 000 or OM Martin. During 1972, Guild changed the body shape to that of a small-jumbo, still a bit over 15" at the lower bout, but deeper overall. In 1973, the first production rosewood F-30R was released in the small-jumbo body shape (see photo of mine below). There were two versions of the F-30R with the small-jumbo body, the first as pictured ('73 to '75), and a later one with a more ornate neck ('76-'78). The 'R' small-jumbo version was only in production from 1973-1978. The mahogany-bodied small-jumbo F-30 was in production from 1972 until 1985. The F-30 model designation was revived in 1998, but reverted back to the 000/OM body shape, and was produced both as an F-30 and F-30R. All versions of the F-30 produced since 1998 have used the 000/OM shape. Important: Do not confuse the F-30 with the JF-30, which had a full 17" jumbo body!
1973 F-30R: