Yeah we did in standard the original is a half step down so it was a stretch to reach the high parts for me. Also I never learned the solo completely like its played on the original which I should really learn.as for the bass outta tune, well next he needs to tune it lol! I've suggested we do it a half step down so it sounds a little better, but my bassist is reluctant. Laziness in bringing an extra bass or changing the tuning really.
What's stopping you from playing the song in the same pitch as the original?
Transposing on a guitar is the simplest of any instrument, simply change positions.
Move the fingering down one fret (1/2 step)

Takes a bit of planning and practice sometimes with songs that use open chords,
I do this all the time with S.R.V, Jimi Hendrix, and lynyrd skynyrd, songs
Sonicly there is no difference when playing one fret lower on the fretboard.

I've often wondered why musicians tune down - the only time it makes sense to me is for wanting a "HEAVY" sound.
If it's to accommodate a vocal range or wood or brass instrument, I'd assume you'd change keys.

But the performance itself was fairly good, Good energy, you looked like you three were having fun. It's missing the second guitar - perhaps a backing track could be used?
You've started to use a lot of processing on your vocals, not a bad thing as I see it as a positive.
And your bass player finally did some back-up singing.

All very positive things.