Hi Pat and welcome.where in Mo are you?
The spot where you mount the TV will depend somewhat on which 16' Scamp
layout you have,do you know?
The spot Norm uses will be OK if you have the same layout that he does but would not be the best if you have the Side Dinette layout for example.
Regardless where the TV goes yo can not really use an inside antenna in your Scamp
as there is metal foil insulation inside the walls under the "Rat Fur" covering the walls.
This prevents any inside antenna from getting the job done.
So that leaves you needing an antenna outside either on the roof or somewhere else.
How you do it just depends on your needs and how you see the nuisance factor of an antenna that you need to put in place each time you park but that you can more easily adjust for best performance or the convenience of a roof mounted one that may be more limited in performance but a lot easier to live with?
I would suggest searching here and reading about this as this is one of the most talked about subjects on here. There are lots of posts and pictures to give you some ideas.