Mine is rusted some on the bottom half. Nothing is leaking, but appears to have done so before?
How tech advanced does one neeed to be to change one?

 

Its not to difficult but it takes some work. To physically remove it there are 4 nuts that hold the brake booster to your pedal assembly. They are under your dash and pretty easy to get to with a long extension. You will also have to detach the brake pedal and its switch. Once that's done the booster should pull off of the firewall in the engine compartment. Then you would have to disconnect the vacuum hose, fluid level sensor, and all of the brake lines. If you replace it with a new brake booster you normally have to bench bleed it in order to get all of the air bubbles out of the booster. Install the new booster and bleed out all four corners of the truck starting with the furthest from the booster and working you way to the closest wheel. If I remember correct Zabeard did one up when he replaced his booster by installing one from a super duty, which helped with the brake pressure.