There is no best and even the "best" P47 is not much in MA conditions. P47 model differences are small enough to make this a matter of cooler skins and cockpit layout. Even the N is not that a different beast at relevant altitudes and besides the somewhat better option of running away/down from/the opponent, I consider it the 'worst' dogfighter of the bunch. Again we are talking about minor differences.
If you want to fly the jug in a fighter role, you are not the cookie cutter, min/max type. That doesn't mean you shouldn't fully use your plane's abilities though. So:
Fuel load is the most important parameter affecting your performance. Learn to cruise with reduced RPM so you can spend most of your time fighting with less than 50% fuel and make it home on fumes. This is most important in the N which is a total pig with more than 50% on board. Just keep in mind that the N's fuel load is more than 5 fully fueled 109s. If you want to save on weight, this is the place. Much better than leaving gun and ammo behind.
The second is the WEP. Do not be tempted to spend the WEP on the climbout, unless you are far far away from the action. Without it you become a Sumo wrestler after 3 days without sleep. Loose the WEP on the N and you turned from a hot rod to a single engined transport.
Guns, oh yes. Some will swear that the weight reduction from 6 gun package and reduced ammo load will win their fights. I much rather reduce my weight by shooting that excess ammo into the enemy instead of leaving it on the ground. Just go trigger happy till the counters are down to 1000, which is the same as the smaller load. Then start to aim.
The 6 guns vs. 8 may help a little if you are a good shot. I find it is much more important to deliver a killing blow when I create the opportunity, than the contribution of the weight reduction in creating that opportunity. Usually, if you don't kill, even dumping all you guns over board will not save you.
