Hi Pappy35,
You are ready to cover 320 sanding is sufficient. I blow all the dust off with my compressor, then wash the whole airframe down with denatured alcohol. I use the hottest setting on an old flat iron without melting the fabric. I keep a rag with me soaked in cold water. As I iron down the fabric , I hit it immediately with the cold rag, it helps to set the adhesive. You are going to love this stuff and it does hide the wood grain.
Thanks,
Fred