The pedal went to the floor and I only get a hint of braking force.

exact same thing happened with my '93

you can use heat to remove the line nuts from the valves, but be careful to to be excessive. i used map gas the first time i had to do those, and one of them sealed shut, and i had to make a jy run. i used propane and pb blaster the last time, and had success.

Something else must have been wrong before the line blew. Master cylinder?

what makes you say that?

My master cylinder only has two lines running in/out of it. Either front/rear or supply and return from ABS pump. (ABS doesn't work).

Dual master cylinder - You shouldn't lose all 4 brakes. Been like that for many decades.

JW - No return line on a master cylinder. Years ago it was front/rear but I think that changed.

2 lines=F/R, 4 lines= diagonal.

When my line blew I lost all my brakes.

I ended up patching it with unions from the rear door back.

Ok, I got a couple parts. $120+ at the dealer. Anodized aluminum or something. Shouldn't rust by the looks of them.