[Southcity]

Are you referring to the steel line fittings (where the steel brake lines terminate) being different sizes? If so, check the steel lines to see how they are routed from the master cylinder. Some setups run a single line from master cylinder which then routes to a T fitting. Other setups may run dual lines from master cylinder. It's possible a previous owner adapted the wrong steel line size for one side by running an adapter from the T fitting or something similar. Photos of your setup (if possible) would be helpful.