Ratty,
Like you, I have also done post-bacc work after law school (though, I practiced for two years before I went back to school). I did 18 months (32 hours) of post-bacc work at my undergrad institution, which included basically the whole pre-med compliment +biochem.
I filled out AMCAS last month and was horrified (though what did I expect) to see that AMCAS automatically averages your Post-Bacc GPA into your undergard GPA. In my case, my science undergard GPA prior to post bacc was something like 2.89 spread over 18 credits taken as a freshamn and sophmore 10 years ago. My Post-bac GPA was 4.0 spread over 32 hours. When the computer averaged everything, my cummulative undergard GPA ended up being 3.48, hardly what I had hoped for.
Although there is a seperate row for bost-bacc GPA on the AMCAS form, I have gotten the impression from calling schools that it is the cummulative they look at when doing initial screenings and determining interviews. So, that's not good.
When I started this, I told myself that I would be competitive if I could get A's in half my classes during Post bacc and B's in the other half. A C, in my estimation, even one of them, I figured would sink me. I am VERY glad that I got all A's, because after seeing how AMCAS figures the GPA's, it could have been a lot worse.
My advice, then, is to work as hard as you can to get all A's. Resist the temptation to say "well, I guess I'm just going to get a B in physics because I am too tired to crack the book again". I think it matters a lot.
Judd