Jim, I've never come across Guild guitars, but that's probably because I'm in the UK - so wouldn't know how good they are - and having never really done proper 'real flames' so can't even help on the paint either.........not doing too well so far huh!
Just wanted to wish you well this project and say that looking at your other work I don't think you'll have any problems doing this job at all
One word of advice would be to take your time on the finishing though

On guitars the finishing is probably as, if not more important, than the artwork.
Good luck with the guitar.............hope you'll post pictures when she's done?
Jim