Hi,
First of all, good luck with your prep! Both of the books that you mention will provide the information that you need to excel on SC and CR. However,
it's not just the materials but how you use the materials. So how you organize yourself will be critical. Is there any reason why you're not investing in an RC book?
Also, the verbal section is always testing your ability to read and comprehend whether in the RC, SC, or CR so you would benefit from reading an article from a solid publication (like the economist) every day to build up your reading skills. The important thing when doing these reading exercises is to read for TOTAL COMPREHENSION. Meaning, if you do not understand a sentence then re-read until you do. Be thinking about premises, conclusions, and assumptions of the article and ultimately the main idea (you can keep a spreadsheet tracking the articles that you have read and the main ideas). Look up words in the dictionary. The writing on the GMAT is similar to the writing in these articles. This reading will help you in all areas of verbal and who knows maybe you will enjoy i:)
Let me know if this makes sense!
HG.
PS: Your question about whether it is possible to achieve a 43 in two months - a qualified yes