Hi Rage thanks for reaching us.
With regard to your question, please consider that it was already discussed in the past in this thread.
Long story short you can set the scene scale simply using
# check the current values for the currently active scene
# for default scene it returns (1.0, 3) where scale is "1.0" and unit is "cm"
print "current scale:", doc[c4d.DOCUMENT_DOCUNIT].GetUnitScale()
# instantiate an UnitScaleData()
sclData = c4d.UnitScaleData()
# set the data accordingly to your needs
# e.g. scale by 10x and set to mm units
# set the proper parameter in the active doc
doc[c4d.DOCUMENT_DOCUNIT] = sclData
# fire an EventAdd()
# check the new value
print "new scale:", doc[c4d.DOCUMENT_DOCUNIT].GetUnitScale()
Finally, to speed up your issues' resolution, I warmly encourage making use of the search function.