The current maximum post size is 32768 characters. That includes formatting BBCode and white space as far as I'm aware as those are characters from a database storage standpoint. Call it around 5k words in Word as a rough benchmark, although that's a very approximate figure estimated off on document I had handy and has no relation to the forum's internal calculations.
Given that limit, the best way to do this is I can think of in SMF as we have it configured here would be an index post that points to the other posts. You can fit a lot of links into that space, and if you have to, you can break the index itself up into multiple posts with the first post pointing to the other indexes.