line lock

moparsegura said
no, the front chamber is smaller- for the rear brakes. The back chamber is a little bigger, for the front brakes

This is what I'm talking about.

http://www.moparmusclemagazine.com/...lling_factory_style_disc_brakes/photo_16.html

If a disc type MC then its easy to figure out which line is for the front compared to the drum MC.