If you have a lot of 'travel' in the brake pedal you might need to replace the vacuum brake boost that sits between the master cylinder and the firewall. I just did mine. It was a pain. Found a master/boost combo kit OE at Autozone for 116. I read a lot of posts that said to remove dash, steering column etc. I didn't want to create more work. I ended up removing 4 bolts to the driver seat for room to lay down on back and look up. I used a 3/8 drive for the 4 bolts holding the booster to firewall behind the dash located above the steering column. First remove the brake lines to the master though and then remove the master from the booster to keep the weight light on existing equipment while you're unbolting the old vacuum booster.
When I put the new master and booster on the brake lines didn't exactly line up so I had to bend them a litte to go in without resistance. Next fill with brake fluid and begin bleeding. Keep adding fluid as you go so you don't run out. It took me amost all day to do it but I saved $300. The only thing I removed was the front driver seat...which allowed me to vacuum under that and spraypaint the feet black again lol. I kept dash and everything else in tact.