How often would I need to reconnect the alternator belt, or charge the batery?
Also note that just reconnecting the belt to charge your battery erases the benefit of driving with the belt off. You may actually get WORSE mileage if you do that. The only advantage to be gained is if you recharge your battery from an external source (I've been using a solar panel).
Also note: the fastest way to destroy a starting battery is to discharge it deeply & repeatedly. You really need a deep-cycle battery to do this mod properly.