Let's see. 100 points in 6 weeks won't be easy - that is a decently large improvement to make in that timeframe - but you're also working on a deadline, so you'll just have to go for it! Keep in mind that you do have that buffer of the month of March, so do your best for 6 weeks but don't absolutely lock yourself into March 1st. If the time comes and you realize you could either (a) take the test March 1st but have the score be closer to 500, or (b) take 2-3 more weeks with a greater chance that your score will be 550+, then you can decide at that point what is more important to you and go forward accordingly.
For quant, start with the Foundations of Math book - if you don't have it, get it. You need to know that backwards and forwards. As you get better with specific areas from that book, you can then revisit the corresponding strategy guides (eg, after you feel really comfortable with the Foundations skills for fractions and percents, then you can move on to the fractions and percents chapters in the Fractions, Decimals and Percents strategy guide).
I'm betting you also likely had some timing problems on quant (almost every does), so read this and start doing what it says:
http://www.manhattangmat.com/blog/index ... anagement/As you get better with the facts and rules and skills (doing calculations, etc), you'll also be trying some OG problems, and you'll want to set up flash cards for yourself in this form:
one side: When I see .....
other side: Then I'll think / do .....
This will help you to learn how to reason your way through these problems. You're going to study / remember what to do or think about when you see certain words or phrases. Almost like learning how to translate a foreign language. :)
In answer to your question about verbal offsetting quant, yes, this is possible, but a school may also take a look at your subscores - they often do when there is a huge difference between the two subscore percentiles. So you should try to improve both - quant because the schools will want to see a better quant score and verbal because it's going to be easier for you to improve on verbal. (It's always easier to improve our strengths.)
But you're going to spend more time on quant - again, because it's lower and because it takes longer to improve our weaknesses.
On the verbal side of things, use the article I gave you in my last post to analyze the verbal side of the test and then tell me your analysis. I agree in general that it sounds like SC is your big strength and CR is your big weakness but I can think of things that would change that. (eg, did you miss some lower-level SC problems? Did you go too quickly on CR and that caused careless mistakes? Maybe you went too quickly on CR because you were too slow on SC or RC or both? Then maybe the problem is really a timing problem with a different Q type. Etc.)
By the way, on verbal you mentioned that you finished early and noticed a lot of careless mistakes. Going too quickly can be just as much of a problem as going too slowly, because it increases the number of careless mistakes you make. So work on that timing and work on being very systematic about your problem-solving process.
Read the careless errors portion of this:
http://www.manhattangmat.com/articles/error-log.cfm