Replace the Dell Streak 5's main board or memory card?

I have 2 dell streak 5. first of them's screen is broken (rest works very well). Second one does not work anymore because of trying to change its operating system (rest of it works very well). I thought instead of changing its screen (it looks more complicated than changing main board) i can transfer first's main board to second. And then i saw this Dell Streak Teardown guide. On step 10 its talking about non-user accessible sd card. My question is instead of changing main board completely can i just transfer this card with plastic opening tools and screwdriver? thanks for your answers