As an organist and bassist, I'm sure you've probably got all the theory pretty much down. That gives you a huge jump start. From that, I would say to just get a chord book and get used to fingerings and such. Playing the bass already, you will see the relation to your bass scales and guitar barre chords (the scales are "built" sround barre chords).
You've already got rhythm, which is awesome, because that's the one thing I never could teach my friends when giving them little mini-lessons.
I would say you have already jumped the major hurdles before you've even started.
Once I had my basics down (chords, changes, etc.) I really leaped forward by playing along with CDs, and in church. Give yourself 20 minutes a day, and you should be playing in church in a few months, no doubt.
The only other thing I can think of is this: when my dad taught me my chords, he would show me 3, then he wouldn't show me anymore until I could change those at will with my eyes closed. Now, this may have been some twisted pleasure thing for him, but it really helped me learn my shords fast.
Good luck, I hope we can help you along.