JDL, your doing a good job especially since you ask a lot of questions and make a good "informed" decision. Your right on the brake line sizes. They work because the "blocks" have the different and correct sizes where the lines go in. No need in spending the big bucks if you don't have to! Look or shop around as your doing and you will save money.
Keep up the good work. We want you to be able to stop without dragging your feet like Fred Flintstone
