Hi Hurley,
Congrats on making it this far down the road, with the end in sight. Here are a couple of suggestions given your time constraints (with apologies if you already do some of these things! I don't know your study background so am going to err on the side of going overboard):
If most of the problems you are missing AND overtime on are DS, then you need to cut yourself off for DS earlier! The GMAT is not a traditional test, and embracing the oddity of the way it is adaptively scored (and accepting that even really high scorers miss CONSIDERABLE numbers of questions) will give you permission to cut and run on certain questions. As you shift to a heavier load of
OG drills/process rather than content (a key step as you get closer to your test date), don't just focus on getting questions right-- focus on identifying questions that you would *probably get wrong and therefore shouldn't waste your time on.* Remember also that a huge chunk of the questions are experimental, so wasting a lot of time on a question that's really rough may yield you zero points anyway!
As for DS and SC eye-glazing, the fix is the same-- having a concrete, repeatable process for each. Do you do splits and re-splits for SC questions? That will help prevent the words-flying-in-your-face approach. Do you list ABCDE out on your scratch paper for the verbal section and cross choices off physically as you identify errors?
For DS, do you grid answer choices? One of the hardest things to conquer for DS is the format, and making the way you process that format automatic (via grids) can really help. Most of the major companies out there will tell you to grid AD/BCE or BD/ACE (you may already know this process, but if not a quick search on these forums will fill you in)...I know some students, especially students who are strong in math, are resistant to these practices, but taking these seemingly simple steps can break down doors. They seem obvious, but they're important. The test is intense, so you want your pen and paper to do all the lifting they can, and conserve your brainpower for higher-level functions. Gridding on DS questions will also serve you really well in situations where you decide that it's in your interest to guess--often, especially on 700+ questions, one of the statements is significantly easier than the other and you can cross of 2-3 choices and choose from the rest without having to stop to think about which choices are left...they're right there on your paper!
As for the larger timing issues-- practice, and practice setting limits for yourself. Timed drills from the
OG, cross-training between different question types, etc. See what forcing yourself to guess at 2 min (or even at 30 sec or 1 min on questions that you are pretty sure you wont' get) will do-- it may not effect your accuracy at all, but allow you the time to finish.
Good luck!