Using Laptop GPS as reference for ArduTracker

Hello,

I’m pretty new to ArduPilot, Mission Planner and UAV’s/drones in general. Hopefully I’m not opening a topic already discussed.
Instead of building an antenna tracker with a Pixhawk I would like to use the ArduTracker (ardunio uno with servo shield) in Mission Planner and already found some good information, but instead of using the fixed tracker home position I would like to use a laptop internal GPS as reference.
Also monitoring the serial traffic form the MP ground station I see only the pan and tilt strings being transmitted. All other parameters on the MP page for the ArduTracker are never being send to the Arduino, not at serial connection, nor during the continuous transmission of pan/til.
Has anybody experience with this and could give me a hint how to get this going? Thanks a lot in advance!

Cheers.

Peter