eja,
if you are looking for antennae arrangement, it depends on what unit you are modeling. some have different arrangements of the roof gear. some are set up as mid-train DPU power, and usually have four large sinclair antennaes in a "V" pattern, but close together, and one in the back of the cab roof, looking at the loco from the front. ex. cp #9526 kato released this model. now, i am not exactly sure which units have what, but they may have all of their ac's with this arrangement. is this the info you were looking for? if anyone finds this info incorrect, let me know! the #9771 in the above link is the same setup.