We haven't included a full template, because one of the interesting features of the GSX.CFG file, is that you don't have to do a complete file, if you don't want to, it's possible to create just a smaller subset of it, if you want to simply change something on an already recognized airplane.
For example, if you want to just disable the default refueling page, it would be enough to create a GSX.CFG file with just these lines:
[aircraft]
refueling = 0
And the rest of the info will be taken from the GSX internal database.