Brake Upgrade Q's

[Springbok]

I am still new to owning a Cobra so I am still in my "learning" phase. After driving the car and looking where I can make some improvements, one of the areas I am looking at are the brakes. I am still trying to figure out my brake system and where I can make some upgrades without overhauling the entire system. I have some basic questions that I was hoping I could get answered.

First some things I DO know about the brake system.

1. Rear end is an 8.8" Ford rear end. There are many kits available to upgrade, I am looking it the Wilwood options.

2. I currently am not 100% sure what master cylinder I have in the car, there are no visible part numbers or markings.

3. I DO have an electric brake booster, but not sure the brand or model.

4. Front brakes are single piston 1978-Up GM Metric Brake Calipers, a pretty base option. The rotors are 11.25in diameter.

5. The wheels are 15".

6. I am not sure if there is a brake balancer in the system, I am still looking.

Some of my initial questions are...

1. Can I upgrade the rear to disc without changing any other components? If not, what would I need to change?

2. Can I upgrade the front without changing any of the other components? If not, what would I need to change?

3. If I change the front brakes, do I reference the front spindle to look for compatibility and fit?

4. What re some of the basic things I should be looking at in order to upgrade?

I know these are vague questions, I am still a noobie but any bits of info always help. I am trying not to overhaul the entire system if possible, Ideally I can just upgrade the brakes at the wheels and not touch the master cylinder and electronic booster.

I have attached pics to give an idea of what I am working with. Pics are of the master cylinder, rear drum, front brakes and electric brake booster.

Thanks in advance for any tips/info!