Venus GPS + Arduino. Kill 3.3V TX during sketch upload
If you have a logic-converter between the Arduino and the GPS then you won't have any problems.

The warning was about having the output from the Tx pin on the GPS possibly being damaged by +5 V from the Arduino, if a previously loaded sketch made it an output and HIGH.

However you could just as easily upload a "do nothing" sketch like this:

int main () { }


That is sound practice anyway, if you are connecting up new hardware and are not sure what the currently-loaded sketch does.