It would be best if you used long drywall screws. Take the back of the guitar off with a prybar (carefully)(you may need to use a hammer and large sharp chisel to get you started.) It is best to run the screws (about 2 dozen very close together) in from the INSIDE of the guitar body into the neck. Go ahead and run some into the 6 string neck also for stability...Put the back in place and secure with fine quality duct tape. Just to be sure pour a gallon of wood glue into the sound hole. Roll your guitar around to make sure the entire INSIDE is coated. Let dry for about a month, string it up and head for Nashville. Sorry about tonight's gig. But, hey! Borrow a Harmony Sovereign and go for it.