[Ovmsdev] GPS antenna direction

The GPS antenna that can be bought for the ovms module from fasttech - what is the best way to mount it? Should the black plastic with "GPS" engraved point towards the sky or can I use double side tape and stick the antenna to the windshield with the label upwards.  Does it really matter? I guess direction of placement for the GSM antenna is not as critical, but any thoughts on it? Nikolay