Brake line questions on a front disc swap.

[j.rigby15r]

Put disc brakes on my 64 that I got through pro performance. Went to hook up the brake lines to the calipers and the line sizes are different. As I never have messed with brake lines before is there an adapter that I need to make this work or what do I do? I have a duel master and proportioning valve. I have never done one of those either so if it has something to do with that please let me know. I have the value mounted to the master but no other lines hooked up. Please advise.