Quarter panels, let's cut em off and put new ones on.

Are you installing skins or full OE style quarters?

OE quarters are easier to install from a welding point of view. It’s more time to remove them, drilling all the spot welds etc. And more time getting everything fit right going back on. But then it’s just spot welds. And most of those are in channels or on lips or behind stuff when the car is assembled.

If you’re doing skins, take your time. Make sure everything you’re welding is bare metal and clean, set a nice consistent gap, and GO SLOW. If you go too fast or work too much in one spot the heat will warp the metal and then it’ll be a real headache to get it straight.