are 47re autos weak?

I have drilled them out before but it's a PITA. I just cut the steel line and flair it and replaced the rubber hose. You could unbolt it and get fittings if you want to get fancy but I just clamp it. Just like they did on your old A and B bodies from the factory. It's not high pressure.
Do you use high pressure line and double clamp them or what?