It appears there may be some peculiarities that make using the GPS Forwarding function problematic. You can configure multiple places to forward that data, but from what I see, they would all have to use the same GPS Format and Sentence Type as that can only be defined once. I do not see a way to change them based on the IP/URL you are sending them to.
Second potential issue is the field length of the Tracking ID field is 4 characters Maximum. That should be at least the number of characters in a MAC address as that is what most tracking devices use to differentiate between devices on a tracking site. Only allowing us 4 characters, will make it more likely someone else will use the same 4 characters on a tracking server and then how would that server know who is sending the data after that? -Bill