I did it years ago on my 85 CJ7 - it wasn't hard. If memory serves, you'll need the master cylinder, brake booster, and bracket. You can buy the whole kit on places like ebay: jeep cj power brakes | eBay
You'll also need an air cleaner that's made for power brakes. The stock on on my CJ hit the master cylinder. They make offset ones for guys with power brakes.
Power brakes were an option on the CJ7s, so you won't have to engineer anything - you're just swapping on factory power brake parts.