Roof repair after storm

[Nancy]

We need to replace the roof on a 1978 14X70 Atlantic
that had its roof taken off by a microburst. There is
another 14 X 70 addition to this in the shape of a ' T '.
The metal peeled off one long side and the two short sides,
hanging on the other long side in places. All the arches
and some insulation was left. We need advice on where to
start. We have been told a truss roof will not be supported
by the walls (I presume they are 2x2 if this is true)
and Butch from BG's Mobile Home Service here said
something about a split-truss roof (??). We were thinking
about putting 2X4 along the edges and down the center
of the arches and then lay plywood over that for starters.
Is this reasonable?? We have not quite decided to metal
or shingle or what from here. Any ideas?? Thank you.