This is the kind of shit I live for. Some background: This is basically the first published stand alone ‘adventure’ as we know them. Notably written by authors from Wee Warriors and published by TSR. I believe there was some controversy in how these things were written / published back in the day and rights and whatnot but I may be misremembering.
This sort of module is all anyone ever needs. Truly. It is incredibly generous to call this a ‘megadungeon’ in any sense it is 170ish rooms across 5 levels and was probably mega for its time. It is small and sparse at 13 pages front and back. You get some background, some tables, some hand drawn maps and all of it is super terse. For the people who hem and haw about minimalism. Do you really need more? This tells you who’s in the room, what they are doing and how good they are doing it. It’s even kind enough to tell you up front to make it your own and how it is merely an outline. Notably there are no wandering monster tables (but it is noted and up to the discretion of the GM). I genuinely think more modern GMs should give this kind of module a read and trust themselves more to figure ‘the rest of it’ out.