Implementation of physical layer

Hi
I am trying to develop physical layer for cooperative MIMO wireless
system.
I have used benchmark (gmsk) as the base platform and trying to bring
about
changes in it.
I have made the packet size of 10 bytes 2 for packet number and 8 for
data
from a certain file for transmission. Now in order to apply combining
techniques at the receiver i need to know that how many bytes or bits
are
received for the above mentioned packet size at the point in the gmsk.py
file after the clock_recovery block considering the default interp and
decim
settings of the usrp used for simple benchmark. How can i find this?