Importance of grades in clinical years as an MD/PhD student?

Anyone have a sense of how important 3rd year grades are for the match, say in a top program in Peds or Internal Medicine if you're MD/PhD?
Board Scores?
Any other factors?

It is all important really, you will be competing with the very best and most of the matches will be good in all areas and many will stand in one area (eg top of class, cell papers, 260+ steps, etc).

I completely agree. Don't let anyone tell you that 3rd year grades aren't important for MD/PhD applicants. The PhD is NOT a "golden ticket" as many suggest. There will be many that doubt your clinical abilities because of your strong research background. Don't give these folks fodder by suggesting that the clerkships are any less important than anything else on your application; if you get honors it will make life a lot easier.