ml370 drive replacement - upgrade

[CA1201429]

I am looking to upgrade my four 9.1gb drives with 36gb ones. I know that if I replace one now it will only function as a 9.1. My questions are if I replace one at a time (they will be 9.1) but once they are all replaced will they function as 36gb? Or will the array have to be reconfigured? If the array has to be reconfigure do I have to reinstall everything? So, in essence, what is the best way to replace my current drives with new ones and have the new ones show us as they are supposed to?
Hope this made sense.
TIA for any assistance.