That's how I play. It's very easy to restring a lefty Fender-style bass as the main problem is the nut, but
usually if the nut is the kind that fit into a slot in the fingerboard(as opposed to the type that fit against the end of the board) you can just swap it around, then its usually just a matter of redoing the bridge saddle intonation.
I mentioned it in another post but, when I remove a Fender nut I heat it with a blow dryer which loosens the glue holding it in place, and it comes out quite easily.
As far as the other style nut, I use 45-105 guage strings and they are usually large enuff that the G string in the original E string nut slot is not a problem, you just need to get some decent files to widen the other slots.