1970 Case CK 580 no brakes

I just bought an old CK 580, the brakes don't work. If I press hard on the lefthand brake, I can slow the tractor a little. The right hand brake isn't hooked up. (All the linkages seem to be there.)

Also, the differential lock isn't hooked up. There is a rod that comes out of the transmission and ends in a lever, the lever is broke off.

Two questions:

How do I fix the brakes, or what should I look for to diagnose why they aren't working?

How do I fix the differential?

Thank you,

Scott

1970 Case CK 580 no brakes