Solder wires onto the FLORA GPS' GND, TX, RX, 3.3V pins. Solder two longer wires to the GND and BAT pads on the FLORA GPS.
Route the two long BAT/GND wires through an unused hold on FLORA (like D9).
Solder these connections and insulate the back of the holder with tape.
Plug in the FLORA via USB and test the GPS circuit according to the FLORA GPS guide.