They may have the same modems but each device may have some hardware differences for the specific MT product. The MT-GL is not identical to the MT-uL which means that a package design for the MT-GL will not (should not) load into an MT-uL (and vice-versa).

If the user purchased a modem for use inside of their custom box then it would not be "aware" of things like GPS, etc. The modem upgrade package must be aware of the different product types and only upgrade products it was intended for.

Steve