Differance in power disc brake vs manual drum brake line?

Can someone please tell me what the differance is in the brake line (hard line) on a 70 e body with manual drums. Vs the line with power disc?
I bought front brake line set for the barracuda. Manual drum. Under frame rail. I
Went to put on the passenger side rubber hose. Won't start...(new hose)
Took hose back off car. So be easy and no bind. Still never even try. Are threads differant size?? Between the 2??

As far as I have seen, I have to believe that all threads are the same size A, B, and E body. Some are smaller and others larger, but all have the same thread pitch to it's size. Call the place where you purchased the hose from to see if the part number given to you is correct. The fitting on the hard line could also be wrong. I've had more problems with new purchased parts that old stuff. Now they have brake line threads that are metric, could have been a mix-up at the manufacturer. The only thing different between power disc and manual drum is the master cylinder and proportional valve.