You packin' this stuff in a van :-). Are you sure you don't need more picks? ;-)

Kidding aside, I like to over-prepare as well. I pack an extension chord, an extra guitar cord, extra batteries for my audio recorder. When somebody says "crap, I forgot my chord" I got 'em covered.

I've made plenty of riffs and solos "my own". In another forum, I posted a recording I made of "China Grove" by the Doobie Brothers. When I was learning this song for the band, I ran out of time to learn the entire solo, so I "faked" the last phrase. The rest I have down note for note. My faked part fits and it's easy for me to play. I challenged people listening to the recording to identify a part that I "made my own". Nobody did, so I say mission accomplished! I did the same thing with "Hard to Handle"...nobody can tell.

As long as you capture the spirit of the original part, nobody will even notice. Unless you want to learn it for your own personal satisfaction, there's no reason not to fake it if you find that easier to do.

Good luck tomorrow night...don't let the nerves get to you, it's all fun. Be chilled and relaxed and don't expect miracles.