Preparation for Executive Assessment and GMAT at the same time

Hi everyone! I am a bit under self-induced time pressure (wasted a lot of time, who cares:) as I am working on application MIT Sloan Fellows accepting EA with a deadline by December 5 and then I would like to try chances with a Stanford accepting GMAT only... Given that EA is similar to GMAT apart from being shorter and valuing IR at the same level as Verbal/Quantitative skills, I am thinking of the following plan - register for EA at the end of November (1 month to go ), prepare for it/register for GMAT at the Dec 15-20 (trick is that GMAT is available in 20 days, whereas EA is available immediately). I already did GMAT in Jan 17 and scored only 36 in Quant (that is my biggest challenge, I am not doing particularly well under time pressure in quant), 39 in verbal and only 5 in IR (honestly not cared much about it, but will have to at EA test), AW was just 4.0 - I did not spend an hour preparing for it....
It seems like I should focus on quantitative part and IR. What you think of this plan?
Is GMAC official preparation course (costs just $35) good for EA preparation? What would you advise for intensive course for GMAT? Official GMAT? Or given my weakness in quants - Manhatan Math preparation? Any thoughts would be appreciated!