Fletch, here is some advice that may be helpful to you as a MS1:
Most G.S. residencies, except for the big name ones, do not care so much about your basic science grades as they do about your USMLE I score. The proverbial advice is that you should try to get at least between a 210-220 to be competitive for G.S. in today's market. Of course the higher the score, the better your options. I'd venture to say that a 220 and above will open many door for you. However realize that this may change in the next few years, depending on which way the popularity for G.S. residency sways.
One of the most important factors in your application will be your 3rd year General Surgery rotation grade. If you Honor this rotation it will help your application tremendously.
Of course, you'll also need some good letters from surgery attendings. My opinion is that it is better to get an excellent letter from an attending that knows you very well, rather than get a mediocre one from a superstar attending/chief who hardly knows you apart from the other med students who rotated through his department. Program directors are not stupid and will realize if you simply got a letter from a well-known attending just so that you could name-drop.
Finally, research helps but is not essential except for the big wig programs. Again doing surgery-related research that you are INTERESTED in (not just to pad your CV) and getting your name on a couple of publications can only help your application.