Is your model already textured in Maya or were you planning to do that part in SketchUp?
Either way, your best bet will likely be to export the model from Maya as a .3DS file and then import the .3DS file into SketchUp.
You might find that the 3DS model ends up being imported with a bunch of extra coplanar diagonal lines and triangulated faces. One of the ruby scripts i downloaded from the ruby library depot is called delcopedges.rb. The script deletes co-planar edges of a model all in one shot. in some cases though, the script causes surfaces to disappear.
Another trick i use is to select all (by tripple clicking), then use soften smooth edges to soften all the normal edges, then go to wireframe view mode, then select the coplanar edges and delete.
-mike



