Welcome to LTG... as you surmised, "BLD" is the abbreviation for "blonde" (NOT bald!)... The D-30 is similar in most specs to the late '70s early '80s G-37; according to Beesley, the G-37 was discontinued in 1986 and the D-30 appeared (in its place) in 1987 (so yours would be a first year). Both had spruce tops, maple sides and arched (laminate) maple backs. Again, according to Beesley, the D-30 had scalloped bracing (the G-37 did not). Note that earlier G-37s (like mine) have mahogany necks and silk-screened logos, while the later G-37s and D-30s have multi-piece maple necks and the Chesterfield logo on the headsrock (D-30 headstock is "tapered," while the G-37 is the older "domed" or "center raised" style).
Unfortunately, the D-30 is too "young" to be included in Hans Moust's "The Guild Guitar Book"... at least in vol I. We all patiently await (some more patiently than others)vol II. Hans is a regular contributor to the forum, and is a wealth of info. If you have more questions... post them up, and he likely will be able to answer them for you. dave