@Jeremy-Palmer Welcome to the forum!
Uploading a GPX file to Google Maps is possible, but it can be tough (Google it). Why don't you make use of MRA's own navigation capabilities? The only thing that basic users cannot do is design routes using the map that is also used for navigation (HERE map). For that, you would need a Gold subscription. However, you can still navigate your routes, but you should be aware that there may be discrepancies between your created route and the navigated route. You are actually warned about this before you start navigating!
You can still take advantage of the offer. I would definitely consider it! Pre-sale Lifetime offer