Sorry for the loss of your monster. As far as mounting goes, most of the time when a catfish is to be mounted, the taxidermist does a fiberglass mold. Taxidermy for catfish does not hold up over the years and will deteriorate. To do a fiberglass mold, you will need a lot of measurements, including but not limited to total length, and girth at 1" intervals. Take lots of pics as well. You might have more luck finding someone to do this type of work. Fiberglass molds look great and will last forever.