After they pulled my trailer into the shop Dan walked me through how he would install it. There is an inconspicuous spot behind the TV that he will mount the router to (which connects to the antenna on the roof).
When I got home I called T-Mobile's help line (just dial "0" to get human) and had them manually activate the sim card since there is no phone device but rather a modem it will be used in.
I may have to go down to the dealer tomorrow, we will see. If not I will definitely find out on Wednesday if this setup works correctly.