Either type will work but if you use the "outdoor type" carpenters glue I beleive that its waterproof. You shouldn't have any worries using the water based polyurethane on the silkspan. Use tooth picks or swabs to wipe away any excess glue before it dries because it can be difficult to sand.

I think that I would start on the tail feathers as a "Warm-Up" to building the rest of the model. When you try out the silkspan application you should cover the bottom surfaces of the wing and tail first. Silkspan also has a grain and you can tell by tearing a corner of the material to see which way the grain runs. You want the grain to run span wise.

If your going to use a glow engine you might want to try and find one of the OS Max Four stroke .20 - .25 size engines. In my opinion it would be a good match and sound real good putting around the bean patch.

PutPutPutPutPutPutPut (Smiles)

This man has a real good handle on building models and a very informative web site. Go and read this post and then follow the link to his website. Paul builds excellent models

How to Build Warren Truss Fuselage Sides