Add ufl connector to internal patch antenna
Find the antenna datasheet, design a pcb on which to properly mount the antenna following the design guidelines, add a section of 50 ohm transmission line from the antenna feed point to a u.fl connector footprint (again, properly designed based on the datasheet), send the design off to oshpark or similar, and solder it up. Or you can try to find a gps antenna that already has a u.fl connector, that would probably be a lot easier.